Low-Loss Millimeter-Wave Interface Comprising a Bare-Die

ABSTRACT

A system for matching impedances of a bare-die Integrated Circuit and bonding wires. A bare-die Integrated Circuit is configured to output or input, at an impedance of Z3, a millimeter-wave signal from three electrically conductive contacts. Three electrically conductive pads, printed on one of the laminas of a Printed Circuit Board (PCB) are connected to the three electrically conductive contacts via three bonding wires respectively, the bonding wires have a characteristic impedance of Z1, wherein Z1&gt;Z3. One of the electrically conductive pads extends to form a transmission line signal trace of length L, the transmission line signal trace having a first width resulting in characteristic impedance of Z2, wherein Z2&gt;Z3. The transmission line signal trace widens to a second width, higher than the first width, after the length of L, decreasing the characteristic impedance of the transmission line signal trace to substantially Z3 after the length L and onwards.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of application Ser. No.12/554,987, filed on Sep. 8, 2009. This application is also acontinuation-in-part of application Ser. No. 12/791,936, filed on Jun.2, 2010. This application also claims the benefit of U.S. ProvisionalPatent Application No. 61/380,217, filed on Sep. 4, 2010, incorporatedherein by reference.

TECHNICAL FIELD

Some of the disclosed embodiments relate to millimeter-wave systems, andmore specifically to a low-loss millimeter-wave interface comprising abare-die.

BACKGROUND

Transporting millimeter-wave signals between a bare-die chip and aPrinted Circuit Board is often challenging, and results in signal loss,impedance miss-match, and electromagnetic noise pickup. Transporting andguiding millimeter-waves and millimeter-wave signals through and betweendifferent elements of a distributed system usually requires a set ofdiscrete components such as backshort surfaces, waveguides, transmissionlines and antennas. Integration of millimeter-wave components andsubstrates often results in expensive and complex systems.

SUMMARY

In one embodiment, a system for matching impedances of a bare-dieIntegrated Circuit and bonding wires includes a bare-die IntegratedCircuit or a heightened bare-die Integrated Circuit configured to outputor input, at an impedance of Z3, a millimeter-wave signal from threeelectrically conductive contacts arranged in a ground-signal-groundconfiguration on an upper side edge of the bare-die Integrated Circuit.Optionally, the spacing between the center point of the electricallyconductive contact of the signal to each of the center points of theelectrically conductive contact of the ground is between 100 and 250microns. Three electrically conductive pads, printed on one of thelaminas of a Printed Circuit Board (PCB) are arranged in aground-signal-ground configuration alongside the upper side edge of thebare-die Integrated Circuit, and connected to the three electricallyconductive contacts via three bonding wires respectively, the bondingwires have a characteristic impedance of Z1, wherein Z1>Z3. Theelectrically conductive pad of the signal extends to form a transmissionline signal trace of length L, the transmission line signal trace havinga first width resulting in characteristic impedance of Z2, whereinZ2>Z3. The transmission line signal trace widens to a second width,higher than the first width, after the length of L, decreasing thecharacteristic impedance of the transmission line signal trace tosubstantially Z3 after the length L and onwards, where Z3 is at most 70%of Z2 and Z3 is at most 70% of Z1. In one embodiment, the system matchesan impedance seen by the bare-die Integrated Circuit at the electricallyconductive contacts with the impedance Z3, by determining L.

In one embodiment, a cavity of depth X is formed in the PCB, goingthrough at least one lamina of the PCB. Three electrically conductivepads are printed on one of the laminas of the PCB. Optionally, theelectrically conductive pads substantially reach the edge of the cavity.Optionally, the bare-die Integrated Circuit or the heightened bare-dieIntegrated Circuit is of thickness X, and the bare-die IntegratedCircuit or the heightened bare-die Integrated Circuit is placed insidethe cavity such that the electrically conductive pads and the upper sideedge containing the electrically conductive contacts are arrangedside-by-side at substantially the same height. In one embodiment, thesystem is configured to transport a millimeter-wave signal between theelectrically conductive contacts and the electrically conductive padsacross a small distance of less than 500 microns, formed between eachelectrically conductive contact and corresponding electricallyconductive pad. In one embodiment, the two electrically conductive padsconnected to the electrically conductive contacts of the ground areelectrically connected, through Vertical Interconnect Access holes, to aground layer below the electrically conductive pads, wherein the groundlayer together with the transmission line signal trace form a Microstriptransmission line. In one embodiment, the same lamina used to carry thetransmission line signal trace and electrically conductive pads on oneside, is the lamina used to carry the ground layer on the opposite side,and the lamina used to carry the transmission line signal trace is madeout of a soft laminate material suitable to be used as a millimeter-waveband substrate in PCB. In one embodiment, the system transports themillimeter-wave signal belonging to a frequency band between 20 GHz and100 GHz, from the electrically conductive contact of the signal to thetransmission line signal trace. In one embodiment, Z1 is between 75 and160 ohm, Z2 is between 75 and 160 ohm, and Z3 is substantially 50 ohm.In one embodiment, the spacing between the center point of theelectrically conductive contact of the signal to each of the centerpoints of the electrically conductive contact of the grounds, issubstantially 150 microns, the width of the transmission line signaltrace up to length L is between 65 and 85 microns, and the spacingbetween the transmission line signal trace up to length L and each ofthe electrically conductive pads of the ground is between 65 and 85microns. In one embodiment, the length L is determined such that thecumulative electrical length, up to the point where the transmissionline signal trace widens, is substantially one half the wavelength ofthe millimeter-wave signal transmitted via the electrically conductivecontact of the signal. In one embodiment, the two electricallyconductive pads connected to the electrically conductive contacts of theground, are electrically connected, using capacitive pad extensions, toa ground layer below the electrically conductive pads, wherein theground layer together with the transmission line signal trace form aMicrostrip transmission line. In one embodiment, a capacitive thickeningalong the transmission line signal trace, and before the transmissionline signal trace widens, is added in order to reduce the length Lneeded to match the impedance seen by the bare-die Integrated Circuit atthe electrically conductive contacts with the impedance Z3.

In one embodiment, a system for matching impedances of a bare-dieIntegrated Circuit and bonding wires includes a bare-die IntegratedCircuit or a heightened bare-die Integrated Circuit configured to outputor input, at an impedance Z3, a millimeter-wave signal from twoelectrically conductive contacts arranged in a side-by-side differentialsignal configuration on an upper side edge of the bare-die IntegratedCircuit. Two electrically conductive pads, printed on one of the laminasof a Printed Circuit Board (PCB), are arranged alongside the upper sideedge of the bare-die Integrated Circuit, and connected to the twoelectrically conductive contacts via two bonding wires respectively, thewires have a characteristic impedance of Z1, wherein Z1>Z3. The twoelectrically conductive pads extend to form a slot-line transmissionline of length L, having a characteristic impedance of Z2, whereinZ2>Z3. Optionally, the slot-line transmission line is configured tointerface with a second transmission line having a characteristicimpedance seen by the slot-line transmission line as substantially Z3.In one embodiment, the system is configured to match an impedance seenby the bare-die Integrated Circuit at the electrically conductivecontacts with the impedance Z3, by determining L.

In one embodiment, a cavity of depth X is formed in the PCB, goingthrough at least one lamina of the PCB. The two electrically conductivepads are printed on one of the laminas of the PCB, the electricallyconductive pads substantially reach the edge of the cavity. The bare-dieIntegrated Circuit or the heightened bare-die Integrated Circuit isoptionally of thickness X, and the bare-die Integrated Circuit is placedinside the cavity such that the electrically conductive pads and theupper side edge containing the electrically conductive contacts arearranged side-by-side at substantially the same height. In oneembodiment, the system is configured to transport a millimeter-wavesignal from the electrically conductive contacts to the electricallyconductive pads across a small distance of less than 500 microns, formedbetween each electrically conductive contact and correspondingelectrically conductive pad. In one embodiment, the lamina used to carrythe slot-line transmission line is made out of a soft laminate materialsuitable to be used as a millimeter-wave band substrate in PCB. In oneembodiment, the system transports the millimeter-wave signal belongingto a frequency band between 20 GHz and 100 GHz, from the electricallyconductive contacts to the slot-line transmission line. In oneembodiment, Z1 is between 120 and 260 ohm, Z2 is between 120 and 260ohm, and Z3 is substantially two times 50 ohm. In one embodiment, thelength L is determined such that the cumulative electrical length, up tothe end of the slot-line transmission line, is substantially one halfthe wavelength of the millimeter-wave signal transmitted via theelectrically conductive contacts. In one embodiment, the secondtransmission line is a Microstrip, and the interface comprisesbalanced-to-unbalanced signal conversion. In one embodiment, Z1 isbetween 120 and 260 ohm, Z2 is between 120 and 260 ohm, Z3 issubstantially two times 50 ohm, and the Microstrip has a characteristicimpedance of substantially 50 ohm.

BRIEF DESCRIPTION OF THE DRAWINGS

The embodiments are herein described, by way of example only, withreference to the accompanying drawings. No attempt is made to showstructural details of the embodiments in more detail than is necessaryfor a fundamental understanding of the embodiments. In the drawings:

FIG. 1A illustrates one embodiment of a laminate waveguide structure;

FIG. 1B illustrates a lateral cross-section of a laminate waveguidestructure;

FIG. 2A illustrates one embodiment of a laminate waveguide structure;

FIG. 2B illustrates a lateral cross-section of a laminate waveguidestructure;

FIG. 3A illustrates a lateral cross-section of a probe printed on alamina and a laminate waveguide structure;

FIG. 3B illustrates some electrically conductive elements of a probeprinted on a lamina and some electrically conductive elements of alaminate waveguide structure;

FIG. 3C illustrates a top view of a transmission line signal tracereaching a probe, and a ground trace or a ground layer;

FIG. 3D illustrates a top view of a coplanar waveguide transmission Linereaching a probe;

FIG. 3E illustrates a lateral cross-section of a probe and a laminatewaveguide structure comprising one lamina;

FIG. 4A illustrates a lateral cross-section of a probe printed on alamina and a laminate waveguide structure;

FIG. 4B illustrates some electrically conductive elements of a probeprinted on a lamina and some electrically conductive elements of alaminate waveguide structure;

FIG. 5 illustrates a cross-section of a laminate waveguide structure andtwo probes;

FIG. 6A illustrates a discrete waveguide;

FIG. 6B illustrates a lateral cross-section of a probe, a laminatewaveguide structure, and a discrete waveguide;

FIG. 7A illustrates one embodiment of a probe and a laminate waveguidestructure;

FIG. 7B illustrates a cross-section of a laminate waveguide structureand a probe;

FIG. 7C illustrates a cross-section of a laminate waveguide structurecomprising one lamina, and a probe;

FIG. 8 illustrates one embodiment of a laminate waveguide structure;

FIG. 9A illustrates one embodiment of a probe and a laminate waveguidestructure;

FIG. 9B illustrates a lateral cross-section of a waveguide laminatestructure;

FIG. 10A illustrates a lateral cross-section of a laminate waveguidestructure, and an Integrated Circuit comprising antenna;

FIG. 10B illustrates a lateral cross-section of a laminate waveguidestructure, and an Integrated Circuit comprising antenna;

FIG. 11A illustrates some electrically conductive elements of a discretewaveguide, a probe, a backshort, and a plurality of VerticalInterconnect Access holes forming an electrically conductive cage;

FIG. 11B illustrates a discrete waveguide;

FIG. 11C illustrates a lateral cross-sections of a discrete waveguide, aprobe, a backshort, and a plurality of Vertical Interconnect Accessholes forming an electrically conductive cage;

FIG. 12A illustrates some electrically conductive elements of a laminatewaveguide structure, a probe, a backshort, and a plurality of VerticalInterconnect Access holes forming an electrically conductive cage;

FIG. 12B illustrates a lateral cross-sections of a laminate waveguidestructure, a probe, a backshort, and a plurality of VerticalInterconnect Access holes forming an electrically conductive cage;

FIG. 13 illustrates a lateral cross-section of a backshort, a laminatewaveguide structure, and a millimeter-wave transmitter device comprisingan integrated radiating element;

FIG. 14 illustrates a lateral cross-section of a backshort, a discretewaveguide, and a millimeter-wave transmitter device comprising anintegrated radiating element;

FIG. 15 illustrates one embodiment of a laminate waveguide structure,two probes, and two backshorts;

FIG. 16 illustrates one embodiment of a laminate waveguide structure,two probes, and two backshorts;

FIG. 17A illustrates a lateral cross-section of a Printed Circuit Board(PCB), a bare-die Integrated Circuit, a bonding wire, and anelectrically conductive pad;

FIG. 17B illustrates a lateral cross-section of a PCB, a heightenedbare-die Integrated Circuit, a bonding wire, and a printed pad;

FIG. 17C illustrates one embodiment of a PCB, a bare-die IntegratedCircuit, three bonding wire, and three printed pads;

FIG. 17D illustrates one embodiment of a bare-die Integrated Circuit,three bonding wires, and three electrically conductive pads;

FIG. 18A illustrates a lateral cross-section of a PCB, a bare-dieIntegrated Circuit, a bonding wire, an electrically conductive pad, anda sealing layer;

FIG. 18B illustrates a lateral cross-section of a PCB, a bare-dieIntegrated Circuit, a bonding wire, a an electrically conductive pad, asealing layer, and Vertical Interconnect Access holes filled with a heatconducting material;

FIG. 19A illustrates one embodiments of a bare die Integrated Circuit,three bonding wires, three electrically conductive pads, and aMicrostrip transmission line;

FIG. 19B illustrates one embodiments of a bare die Integrated Circuit,three bonding wires, three electrically conductive pads, and a coplanartransmission line;

FIG. 19C illustrates one embodiments of a bare die Integrated Circuit,two bonding wires, two electrically conductive pads extended into acoplanar or a slot-line transmission line, and a probe;

FIG. 20 illustrates a lateral cross-section of a laminate structure, abare-die Integrated Circuit, bonding wire, electrically conductive pad,a transmission line signal trace, a probe, a sealing layer, a backshort,Vertical Interconnect Access holes forming an electrically conductivecage, and a laminate waveguide structure;

FIG. 21 illustrates a lateral cross-section of a laminate structure, aflip chip, electrically conductive pad, a transmission line signaltrace, a probe, a sealing layer, a backshort, Vertical InterconnectAccess holes forming an electrically conductive cage, and a laminatewaveguide structure;

FIG. 22 illustrates a lateral cross-section of a laminate structure, abare-die Integrated Circuit, electrically conductive pad, a transmissionline signal trace, a probe, a sealing layer, a backshort, VerticalInterconnect Access holes forming an electrically conductive cage, and adiscrete waveguide;

FIG. 23 illustrates a lateral cross-section of a laminate structure, abare-die Integrated Circuit, electrically conductive pad, a probe, asealing layer, a backshort, Vertical Interconnect Access holes formingan electrically conductive cage, and a discrete waveguide;

FIG. 24A illustrates a top view of a bare-die Integrated Circuit, threebonding wires, three electrically conductive pads, and transmission linesignal trace.

FIG. 24B illustrates one embodiment of using a Smith chart;

FIG. 25 illustrates a top view of a bare-die Integrated Circuit, threebonding wires, three electrically conductive pads, and transmission linesignal trace comprising a capacitive thickening;

FIG. 26 illustrates a top view of a bare-die Integrated Circuit, twobonding wires, two electrically conductive pads, one slot-linetransmission line, one balanced-to-unbalanced signal converter, and atransmission line;

FIG. 27A illustrates one embodiment of a laminate waveguide structure;

FIG. 27B illustrates a lateral cross-section of a laminate waveguidestructure, and additional laminas comprising a probe and electricallyconductive pads, before being pressed together into a PCB;

FIG. 27C illustrates a lateral cross-section of a laminate waveguidestructure, and additional laminas comprising a probe and electricallyconductive pads, after being pressed together into a PCB;

FIG. 27D illustrates one embodiment of a laminate waveguide structure,and additional laminas comprising a probe and electrically conductivepads, after being pressed together into a PCB;

FIG. 27E illustrates a lateral cross-section of a laminate waveguidestructure, additional laminas comprising a probe, electricallyconductive pads, and a cavity formed by drilling a hole in theadditional laminas;

FIG. 27F illustrates one embodiment of a laminate waveguide structure,additional laminas comprising a probe, electrically conductive pads, anda cavity formed by drilling a hole in the additional laminas;

FIG. 27G illustrates one embodiment of a bare-die Integrated Circuit,three boning wires, three electrically conductive pads, and atransmission line signal trace;

FIG. 27H illustrates one embodiment of a laminate structure, a bare-dieIntegrated Circuit, two boning wires, two electrically conductive pads,extending into a slot-line transmission line, and a printed probe;

FIG. 28A illustrates a flow diagram describing one method forconstructing a PCB comprising a laminate waveguide structure and aprobe;

FIG. 28B illustrates a flow diagram describing one method forconstructing a PCB comprising a laminate waveguide structure, a probe,and a bare-die Integrated Circuit; and

FIG. 28C illustrates a flow diagram describing one method forinterfacing between a bare-die Integrated Circuit and a PCB.

DETAILED DESCRIPTION

FIG. 1A and FIG. 1B illustrate one embodiment of a laminate waveguidestructure configured to guide millimeter-waves through laminas. FIG. 1Bis a lateral cross-section of a laminate waveguide structure illustratedby FIG. 1A. Typically such structure shall include at least two laminas.In FIG. 1B three laminas 110, 111, 112 belonging to a laminate waveguidestructure are illustrated by way of example. A cavity 131 is formedperpendicularly through the laminas. An electrically conductive plating121 is applied on the insulating walls of cavity 131. The electricallyconductive plating 121 may be applied using PCB manufacturingtechniques, or any other techniques used to deposit or coat anelectrically conductive material on inner surfaces of cavities made inlaminas. The cavity 131 is operative to guide millimeter-waves 140injected at one side of the cavity to the other side of the cavity. Inone embodiment, the laminas 110, 111, and 112 belong to a PrintedCircuit Board (PCB).

FIG. 2A and FIG. 2B illustrate one embodiment of a laminate waveguidestructure configured to guide millimeter-waves through the laminas ofthe structure. FIG. 2B is a lateral cross-section of a laminatewaveguide structure illustrated by FIG. 2A. Electrically conductivesurfaces 126 are printed on at least two laminas illustrated as threelaminas 110 k, 111 k, 112 k by way of example. The electricallyconductive surfaces 126 extend outwards from an electrically conductiveplating 126 b applied on an inner surface of a cavity 141 formedperpendicularly through the laminas of the laminate waveguide structure.The electrically conductive surfaces 126 are electrically connected tothe electrically conductive plating 126 b. The electrically conductivesurfaces 126 may be printed on the laminas using any appropriatetechnique used in conjunction with PCB technology. Optionally, VerticalInterconnect Access (VIA) holes 129 go through the laminas 110 k, 111 k,112 k and the electrically conductive surfaces 126. The VIA holes 129may be plated or filled with electrically conductive material connectedto the electrically conductive surfaces 126, and are located around thecavity 141 forming an electrically conductive cage. In one embodiment,the electrically conductive cage is operative to enhance theconductivity of the electrically conductive plating 126 b. In oneembodiment, the cavity 141 is operative to guide millimeter-wavesinjected at one side of the cavity to the other side of the cavity.

In one embodiment, the cavity 141 is dimensioned to form a waveguidehaving a cutoff frequency above 20 GHz. In one embodiment, the cavity141 is dimensioned to form a waveguide having a cutoff frequency above50 GHz. In one embodiment, the cavity 141 is dimensioned to form awaveguide having a cutoff frequency above 57 GHz.

In one embodiment, a system for injecting and guiding millimeter-wavesthrough a Printed Circuit Board (PCB) includes at least two laminasbelonging to a PCB. An electrically conductive plating is applied on theinsulating walls of a cavity formed perpendicularly through the at leasttwo laminas. Optionally, a probe is located above the cavity printed ona lamina belonging to the PCB. In one embodiment, the cavity guidesmillimeter-waves injected by the probe at one side of the cavity to theother side of the cavity.

In one embodiment, electrically conductive surfaces are printed on theat least two laminas, the electrically conductive surfaces extendoutwards from the cavity, and are electrically connected to theelectrically conductive plating. At least 10 Vertical InterconnectAccess (VIA) holes go through the at least two laminas and theelectrically conductive surfaces. The VIA holes are plated or filledwith electrically conductive material, which is connected to theelectrically conductive surfaces, and the VIA holes are located aroundthe cavity forming an electrically conductive cage.

FIG. 3A, FIG. 3B, and FIG. 3C illustrate one embodiment of a probe 166printed on a lamina 108 c and configured to radiate millimeter-waves 276into a laminate waveguide structure similar to the laminate waveguidestructure illustrated by FIG. 2A and FIG. 2B. The probe 166 is locatedabove the laminate waveguide structure, such that at least some of theenergy of the millimeter-waves 276 is captured and guided by thelaminate waveguide structure. Optionally, the probe 166 is simply ashape printed on one of the laminas 108 c as an electrically conductivesurface, and configured to convert signals into millimeter-waves 276. Itis noted that whenever a probe is referred to as transmitting orradiating, it may also act as a receiver of electromagnetic waves. Insuch a case, the probe converts received electromagnetic waves intosignals. Waveguides and laminate waveguide structures are also operativeto guide waves towards the probe.

In one embodiment, lamina 108 c used to carry the probe 166 on one side,is also used to carry the ground trace 156 on the opposite side, and thelamina 108 c carrying probe 166 is made out of a soft laminate materialsuitable to be used as a millimeter-wave band substrate in PCB. It isnoted that the term “ground trace” and the term “ground layer” are usedinterchangeably. In one embodiment, lamina 108 c, which carries probe166 and ground trace 156 or ground layer 156 and acts as a substrate, ismade out of a material selected from a group of soft laminate materialsuitable to be used as a millimeter-wave band substrate in PCB, such asRogers® 4350B available from Rogers Corporation Chandler, Ariz., USA,Arlon CLTE-XT, or Arlon AD255A available from ARLON-MED RanchoCucamonga, Calif., USA. Such material does not participate in theelectromagnetic signal path of millimeter-waves. In one embodiment, onlythe probe carrying lamina 108 c is made out of soft laminate materialsuitable to be used as a millimeter-wave band substrate in PCB, whilethe rest of the laminas in the PCB, such as 109 c, may be made out ofmore conventional materials such as FR-4.

FIG. 3D illustrates one embodiment of a printedCoplanar-Waveguide-Transmission-Line 166 e reaching a probe 166 d. Probe166 d may be used instead of probe 166. The ground 157 a—signal167—ground 157 b structure makes a good candidate for interfacing tomillimeter-wave device ports.

In one embodiment, a system for injecting and guiding millimeter-wavesthrough a PCB includes at least one lamina belonging to a PCB. The atleast one lamina includes a cavity shaped in the form of a waveguideaperture. An electrically conductive plating is applied on theinsulating walls of the cavity. Optionally a probe is located above thecavity and printed on a lamina belonging to the PCB. In one embodiment,the cavity guides millimeter-waves injected by the probe at one side ofthe cavity to the other side of the cavity.

FIG. 3E illustrates one embodiment of a probe 166 b configured toradiate electromagnetic millimeter-waves 276 b into a laminate waveguidestructure comprising one lamina 109 v having a cavity. Electricallyconductive plating 127 b is applied on the inner walls of the cavity.The probe 166 b is optionally located above the laminate waveguidestructure, such that at least some of the energy of the millimeter-waves276 b is captured and guided by the laminate waveguide structure. In oneembodiment, the probe 166 b is of a Monopole-Feed type. In oneembodiment, the probe 166 b is of a Tapered-Slotline type. In oneembodiment, a transmission line signal trace reaching the probe belongsto a Microstrip. It is noted that a probe is usually illustrated as theending of a transmission line, wherein the ending is located above awaveguide aperture. However, a probe may also be simply a portion of atransmission line such as a Microstrip, wherein the portion passes overthe aperture without necessarily ending above the aperture. In thiscase, the portion of the line departs from a ground layer or groundtraces when passing over the aperture; this departure producesmillimeter-waves above the aperture when signal is applied.

Referring back to FIG. 3A, in one embodiment, the conductivity of theelectrically conductive plating 127 forming the inner surface of thewaveguide is enhanced using a VIA cage comprising VIA holes 129 a filledor plated with electrically conductive material. In one embodiment, aground layer 156 or at least one ground trace associated with atransmission line signal trace 166 t forms a transmission line formillimeter waves, the transmission line reaching the probe 166.Optionally, the ground layer 156 is electrically connected to at leastone electrically conductive surface 127 s, and the transmission linecarries a millimeter-wave signal from a source connected to one end ofthe transmission line to the probe 166. In one embodiment, VIA holes 129a filled with electrically conductive material electrically connect theelectrically conductive plating 127 to the ground layer or ground trace156. In one embodiment, the at least two laminas are PCB laminas,laminated together by at least one prepreg lamina. In one embodiment,the at least two laminas are PCB laminas, out of which at least one is aprepreg bonding lamina. In one embodiment, some of the VIA holes 129 aare used to electrically interconnect a ground trace 156 withelectrically conductive plating 127. Ground trace or ground layer 156,together with a transmission line signal trace 166 t reaching the probe166, may form a transmission line configured to carry a millimeter-wavesignal from a source into the laminate waveguide structure.

In one embodiment, lamina 108 c may be laminated to one of the laminasof the waveguide structure using a prepreg bonding lamina (element 109c), such as FR-2 (Phenolic cotton paper), FR-3 (Cotton paper and epoxy),FR-4 (Woven glass and epoxy), FR-5 (Woven glass and epoxy), FR-6 (Matteglass and polyester), G-10 (Woven glass and epoxy), CEM-1 (Cotton paperand epoxy), CEM-2 (Cotton paper and epoxy), CEM-3 (Woven glass andepoxy), CEM-4 (Woven glass and epoxy) or CEM-5 (Woven glass andpolyester). It is noted that the term “lamina” is used in associationwith both substrate laminas and prepreg bonding laminas throughout thespec. A laminate structure may comprise a combination of both types oflaminas, as usually applicable to PCB. It is noted that the laminarelated processes associated with making VIA holes, cavities,electrically conductive plating, and printing of electrically conductivesurfaces, are well known in the art, and are readily implemented in thePCB industry.

In one embodiment, electrically conductive surfaces 127 s are printed onlaminas associated with electrically conductive plating 127. Thesurfaces 127 s extend outwards from a cavity and are electricallyconnected to the electrically conductive plating 127. A ground layer ora ground trace 156 associated with a transmission line signal trace 166t forms a transmission line for millimeter-waves, the transmission linereaching the probe 166. Optionally, the ground trace 156 is electricallyconnected to at least one of the electrically conductive surfaces 127 s,and the transmission line carries a millimeter-wave signal from a sourceconnected to one end of the transmission line to the probe 166.

It is noted that throughout the specifications conductive surfaces,probes, traces, or layers may be referred to as being printed. Printingmay refer to any process used to form electrically conductive shapes onlaminas of PCB, such as chemical etching, mechanical etching, ordirect-to-PCB inkjet printing.

FIG. 4A and FIG. 4B illustrate one embodiment of a laminate structureconfigured to guide millimeter-waves through the laminas of thestructure. Electrically conductive surfaces 125 are printed on at leasttwo laminas. The surfaces extend outwards from an electricallyconductive plating 125 b applied on an inner surface of a cavity formedwithin the laminate structure. The surfaces are electrically connectedto the electrically conductive plating 125 b. The cavity is operative toguide millimeter-waves 175 injected by a probe 165 at one side of thecavity to the other side of the cavity. Optionally, a ground layer or aground trace 155 associated with a transmission line signal trace 165 b,forms a transmission line for millimeter-waves. Optionally, the groundlayer or ground trace 155 is electrically connected to at least one ofthe electrically conductive surfaces 125 using VIA holes 129 e filledwith electrically conductive material. Alternatively, the ground layeror ground trace 155 is a surface printed on the same side of a laminacarrying one of the electrically conductive surfaces 125, and the one ofthe electrically conductive surfaces 125 is a continuation of the groundlayer or ground trace 155. Optionally, the transmission line isconfigured to carry a millimeter-wave signal 185 from one end oftransmission line signal trace 165 b to the probe 165. Millimeter-wavesignal 185 is then converted by probe 165 into millimeter-waves 175.

In one embodiment, a receiver probe is located below a cavity, andprinted on a lamina belonging to a laminate structure. The receiverprobe receives millimeter-waves injected to the cavity by a probelocated above the cavity.

FIG. 5 illustrates one embodiment of a laminate structure configured togenerate millimeter-waves 172 b, inject them through one end of a cavityformed within the laminate structure, guide the millimeter-waves 172 bthrough the cavity, and receive them at the other end of the cavity. Anexemplary laminate structure comprising laminas 108A, 109A, 110A, 111A,112A, 113A and 114A, a cavity, plated with electrically conductiveplating 122, is formed within laminas 110A, 111A and 112A, a probe 162printed on lamina 109A above the cavity, and a receiving probe 161printed on lamina 113A below the cavity. Millimeter-wave signal 172 a iscarried by the probe 162 over the cavity, and radiated into the cavityas millimeter-waves 172 b. Optionally, the millimeter-waves 172 b arepicked up by the receiving probe 161, which converts it back into amillimeter-wave signal 172 c carried by the receiving probe 161. Groundlayers or ground traces 152, 151, electrically coupled to theelectrically conductive plating, may be used to form transmission linesreaching probe 162 and receiving probe 161 respectively. Thetransmission lines may be used in carrying the signals 172 a and 172 c.It is noted that the signal path is reciprocal, such that receivingprobe 161 may radiate waves to be received by probe 162 via thewaveguide.

In one embodiment, a discrete waveguide is located below the cavity andas a continuation to the cavity. The discrete waveguide passes-throughwaves guided by the cavity into the discrete waveguide.

FIG. 6A and FIG. 6B illustrate one embodiment of a laminate structureconfigured to generate millimeter-waves, inject the waves through oneend of a cavity formed within a laminate structure, and guide the wavesthrough the cavity into a discrete waveguide attached as continuation tothe cavity. An exemplary laminate structure comprising laminas 108B,109B, 110B, 111B and 112B, a cavity formed within laminas 110B, 111B and112B; the cavity is plated with electrically conductive plating 123, aprobe 163 printed on lamina 108B, and a discrete waveguide 195 attachedto lamina 112B, such that the apertures of the discrete waveguide andthe cavity substantially overlap. Optionally, millimeter-wave signal 173a is radiated by the probe 163 into the cavity, and propagates throughthe cavity as millimeter-waves 173 a. Optionally, millimeter-waves 173 athen enter the discrete waveguide, and continues propagating there asmillimeter-waves 173 b.

In one embodiment, a system for injecting and guiding millimeter-wavesthrough a PCB includes a plurality of VIA holes passing through at leasttwo laminas of a laminate structure belonging to a PCB. The VIA holesare placed side by side forming a contour of a waveguide aperture, andthe laminas are at least partially transparent to at least a range ofmillimeter-wave frequencies. The VIA holes are plated or filled with anelectrically conductive material, forming an electrically conductivecage enclosing the contour of the waveguide aperture. Optionally, thesystem further includes a probe located above the electricallyconductive cage, and printed on a lamina belonging to the laminatestructure.

In one embodiment, the electrically conductive cage guidesmillimeter-waves, transmitted by the probe, through the at least twolaminas.

FIG. 7A and FIG. 7B illustrate one embodiment of a laminate structureconfigured to guide millimeter-waves through a cage of VIA holes filledwith electrically conductive material, embedded within the laminas ofthe structure. A plurality of VIA holes 120 j pass through at least twolaminas 110 j, 111 j, and 112 j of a pressed laminate structurebelonging to a PCB (three laminas are illustrated by way of example).The VIA holes 120 j are placed side by side forming a contour of awaveguide aperture, and the laminas 110 j, 111 j, 112 j are at leastpartially transparent to at least some frequencies of millimeter-waves.Optionally, the VIA holes 120 j are plated or filled with anelectrically conductive material, and therefore form an electricallyconductive cage enclosing the contour of the waveguide aperture.Optionally, a probe 163 j is located above the electrically conductivecage, and printed on lamina 109 j belonging to the laminate structure.Optionally, the electrically conductive cage guides millimeter-waves 140j radiated by the probe 163 j through the at least two laminas 110 j,111 j, and 112 j.

In one embodiment, a system for guiding millimeter-waves through a PCBincludes a plurality of VIA holes passing through at least one lamina ofa pressed laminate structure belonging to a PCB. The VIA holes areplaced side by side forming a contour of a waveguide aperture, and thelamina is at least partially transparent to at least a range ofmillimeter-wave frequencies. Optionally, the VIA holes are plated orfilled with an electrically conductive material, forming an electricallyconductive cage enclosing the contour of the waveguide aperture.Optionally, a probe is located above the electrically conductive cage,and printed on a lamina belonging to the laminate structure.

In one embodiment, the electrically conductive cage guidesmillimeter-waves, transmitted by the probe, through the at least onelamina.

FIG. 7C illustrates one embodiment of a laminate structure configured toguide millimeter-waves through an electrically conductive cage of VIAholes filled with electrically conductive material, embedded within atleast one lamina of structure PCB. An electrically conductive cage 120 tis formed in at least one lamina 110 t of the PCB. In one embodiment,the electrically conductive cage 120 t forms a waveguide. Optionally,millimeter-waves 140 t are formed by a probe 163 t, and are guided bythe waveguide.

In one embodiment, a cavity is confined by an electrically conductivecage, the cavity going through at least two laminas, andmillimeter-waves are guided through the cavity.

FIG. 8 illustrates one embodiment of the laminate structure illustratedby FIGS. 7A and 7B, with the exception that a cavity 149 c is formedperpendicularly through at least two laminas, and millimeter waves 149are guided by an electrically conductive cage, made from VIA voles,through the cavity.

In one embodiment, electrically conductive surfaces are printed on theat least two laminas, such that the VIA holes pass through theelectrically conductive surfaces, and the electrically conductivesurfaces enclose the contour.

FIG. 9A and FIG. 9B illustrate one embodiment of the laminate structureillustrated by FIG. 7A and FIG. 7B, with the exception that electricallyconductive surfaces 151 are printed on at least two laminas. VIA holespass through the electrically conductive surfaces 151, such that theelectrically conductive surfaces 151 enclose the contour of thewaveguide aperture.

In one embodiment, a system for injecting and guiding millimeter-wavesthrough a PCB includes at least two laminas belonging to a PCB. Thelaminas are optionally contiguous and electrically insulating. Anelectrically conductive plating is applied on the insulating walls of acavity formed perpendicularly through the laminas. The electricallyconductive plating and the cavity form a waveguide. An antenna isembedded inside an Integrated Circuit. The antenna is located above thecavity. The Integrated Circuit is optionally soldered to electricallyconductive pads printed on a lamina belonging to the PCB and locatedabove the laminas through which the cavity is formed.

In one embodiment, the cavity guides millimeter-waves injected by theantenna at one side of the cavity to the other side of the cavity.

In one embodiment, the Integrated Circuit is a flip-chip orSolder-Bumped die, the antenna is an integrated patch antenna, and theintegrated patch antenna is configured to radiate towards the cavity.

FIG. 10A illustrates one embodiment of a laminate waveguide structurecomprising electrically conductive plating 124, configured to guidemillimeter-waves 174, in accordance with some embodiments. An IntegratedCircuit 200 comprising an antenna 210 is used to radiatemillimeter-waves 174 into a cavity formed though laminas. Optionally, anantenna 210 is located above the laminas though which the cavity isformed, and the Integrated Circuit 200 is optionally soldered to padsprinted on a lamina located above the laminas though which the cavity isformed. In one embodiment, the Integrated Circuit 200 is a flip-chip orSolder-Bumped die, the antenna 210 is an integrated patch antenna, andthe integrated patch antenna is configured to radiate towards thecavity.

In one embodiment, electrically conductive surfaces are printed on theat least two laminas, the electrically conductive surfaces extendingoutwards from the cavity, and are electrically connected to theelectrically conductive plating. VIA holes go through the at least twolaminas and the electrically conductive surfaces, the VIA holes areoptionally plated or filled with electrically conductive materialelectrically connected to the electrically conductive surfaces, and theVIA holes are located around the cavity forming an electricallyconductive cage extending the waveguide above the cavity towards theIntegrated Circuit.

In one embodiment, at least some of the electrically conductive pads areground pads electrically connected to ground bumps of the Flip Chip orSolder Bumped Die, and the VIA holes extending from the waveguidereaching the ground pads. Optionally, the electrically conductivematerial is electrically connected to the ground bumps of the Flip Chipor Solder Bumped Die.

FIG. 10B illustrates one embodiment of the laminate waveguide structureillustrated by FIG. 10A, with the exception that electrically conductivesurfaces 126 y are printed on at least two of the laminas, extendingoutwards from the cavity, and are electrically connected to theelectrically conductive plating. VIA holes 129 y go through the at leasttwo laminas and the electrically conductive surfaces 126 y. Optionally,the VIA holes 129 y are plated or filled with electrically conductivematerial electrically connected to the electrically conductive surfaces126 y, and the VIA holes 129 y located around the cavity forming aneclectically conductive cage in accordance with some embodiments.

In one embodiment, the electrically conductive cage extends above thecavity and lengthens the laminate waveguide structure. In one embodimentthe electrically conductive cage extends to the top of the PCB throughground pads 127 y on the top lamina. In one embodiment the electricallyconductive cage connects to ground bumps 128 y of the IntegratedCircuit, creating electrical continuity from the ground bumps 128 y ofthe Integrated Circuit to the bottom end of the cavity.

In one embodiment, electrically conductive cage made from VIA holeswithin a PCB extends the length of a waveguide attached to the PCB. Thecage seals the waveguide with an electrically conductive surfaceattached to the VIA cage. The electrically conductive surface is printedon one of the laminas of the PCB, such that both the electricallyconductive cage and the electrically conductive surface are containedwithin the PCB. Optionally, a probe is printed on one of the laminas ofthe PCB. The probe is located inside the electrically conductive cage,such that transmitted radiation is captured by the waveguide, and guidedtowards the unsealed end of the waveguide.

In one embodiment, a system for directing electromagneticmillimeter-waves towards a waveguide using an electrically conductiveformation within a Printed Circuit Board (PCB) includes a waveguidehaving an aperture, and at least two laminas belonging to a PCB. A firstelectrically conductive surface is printed on one of the laminas andlocated over the aperture such that the first electrically conductivesurface covers at least most of the aperture. A plurality of VerticalInterconnect Access (VIA) holes are filled or plated with anelectrically conductive material electrically connecting the firstelectrically conductive surface to the waveguide, forming anelectrically conductive cage over the aperture. A probe is optionallyprinted on one of the laminas of the PCB and located inside the cage andover the aperture.

In one embodiment, the system directs millimeter-waves, transmitted bythe probe, towards the waveguide. In one embodiment, the waveguide is adiscrete waveguide attached to the PCB, and electrically connected tothe electrically conductive cage.

FIG. 11A, FIG. 11B, and FIG. 11C illustrate one embodiment of a systemconfigured to direct millimeter-waves towards a discrete waveguide usingan electrically conductive formation within a PCB. The PCB isillustrated as having laminas 320, 321, 322, 323 and 324 by way ofexample, and not as a limitation. A discrete waveguide 301 is attachedto a lamina 324 belonging to a PCB, optionally via an electricallyconductive ground plating 310 printed on lamina 324, and such that theaperture 330 of the discrete waveguide 301 is not covered by theelectrically conductive ground plating 310. A first electricallyconductive surface 313, also referred to as a backshort or a backshortsurface, is printed on lamina 322, and located over the aperture 330.The first electrically conductive surface 313 has an area at least largeenough to cover most of the aperture 330, and optionally cover theentire aperture 330. A plurality of VIA holes 311 (not all VIA holes areillustrated or have reference numerals), filled or plated with anelectrically conductive material, are used to electrically connect thefirst electrically conductive surface 313 to the discrete waveguide 301.An electrically conductive cage 302 is formed over the aperture 330 by acombination of the VIA holes 311 filled or plated with an electricallyconductive material and the first electrically conductive surface 313.The electrically conductive cage 302 creates an electrical continuitywith the discrete waveguide 301, and substantially seals itelectromagnetically. It is noted that the entire electrically conductivecage 302 is formed within the PCB. A probe 312 is optionally printed onone of the laminas located between lamina 322 and the discretewaveguide, such as lamina 342. The probe 312 is located inside theelectrically conductive cage 302 and over the aperture 330. In oneembodiment, the probe 312 enters the electrically conductive cage 302through an opening 331 that does not contain VIA holes. A signalreaching the probe 312 is radiated by the probe 312 inside theelectrically conductive cage 302 as millimeter-waves 335. Theelectrically conductive cage 302 together with the discrete waveguide301 are configured to guide the millimeter-waves 335 towards theunsealed end of the discreet waveguide 301. The electrically conductivecage 302 prevents energy loss, by directing radiation energy towards theunsealed end of the discrete waveguide 301.

In one embodiment, the first electrically conductive surface 313 is notcontinuous, and is formed by a printed net or printed porous structureoperative to reflect millimeter-waves.

FIG. 12A and FIG. 12B illustrate one embodiment of a system configuredto direct electromagnetic millimeter-waves towards a laminate waveguidestructure, using an electrically conductive formation within the PCB. Alaminate waveguide structure 330 c is included. The laminate waveguidestructure 330 c has an aperture 330 b. At least two laminas 348, 349,350 belonging to a PCB are also included. A first electricallyconductive surface 361 is printed on one of the laminas, such as lamina348, and is located over the aperture 330 b such that the firstelectrically conductive surface 361 covers at least most of the aperture330 b. A plurality of Vertical Interconnect Access (VIA) holes 371 arefilled or plated with an electrically conductive material electricallyconnecting the first electrically conductive surface 361 to the laminatewaveguide structure 330 c, forming an electrically conductive cage 302 bover the aperture 330 b. A probe 362 is optionally printed on one of thelaminas of the PCB and located inside the cage 302 b and over theaperture 330 b.

In one embodiment, the laminate waveguide structure 330 c within the PCBincludes at least one additional lamina, such as laminas 351, 352, 353,354 through which the laminate waveguide structure 330 c is formed, theat least one additional lamina belongs to the PCB, and has a cavity 330d shaped in the form of the aperture 330 b. Optionally, an electricallyconductive plating 380 is applied on the walls of the cavity 330 d. Thecavity 330 d is located below the electrically conductive cage 302 b.

In one embodiment, additional electrically conductive surfaces 380 b areprinted on the at least one additional lamina 351, 352, 353, 354. Theadditional electrically conductive surfaces 380 b extend outwards fromthe cavity 330 d, and are electrically connected to the electricallyconductive plating 380, wherein the VIA holes 371 extend through theadditional electrically conductive surfaces 380 b and around theelectrically conductive plating 380.

In one embodiment, the thickness of the lamina carrying the firstelectrically conductive surface, such as lamina 348 or lamina 322, isoperative to best position the first electrically conductive surfacerelative to the probe 362 in order to optimize millimeter-wave energypropagation through the waveguide and towards the unsealed end of thewaveguide, optionally at a frequency band between 20 GHz and 100 GHz. Inone embodiment, the frequency band between 20 GHz and 100 GHz is 57GHz-86 GHz (29 GHz).

In one embodiment, a ground layer or at least one ground trace 362 cassociated with a transmission line signal trace 362 b forms atransmission line for millimeter-waves, reaching the probe 362.Optionally, the ground trace 362 c is electrically connected to at leastone of the additional electrically conductive surfaces 380 b. In oneembodiment, the transmission line carries a millimeter-wave signal froma source connected to one end of the transmission line to the probe 362.In one embodiment, the ground layer or at least one ground trace 362 cis connected to at least one of the additional electrically conductivesurfaces 380 b through at least one of the VIA holes 371, or through atleast one additional VIA hole not illustrated.

In one embodiment, the same lamina 350 used to carry the probe 362 onone side, is the lamina used to carry the ground trace 362 c on theopposite side. Optionally, the lamina 350 carrying the probe is made outof a soft laminate material suitable to be used as a millimeter-waveband substrate in PCB, such as Rogers® 4350B, Arlon™ CLTE-XT, or ArlonAD255A. In one embodiment, the aperture 330 b is dimensioned to resultin a laminate waveguide structure 330 c having a cutoff frequency above20 GHz.

FIG. 13 illustrates one embodiment of a system for directingelectromagnetic millimeter-waves towards a waveguide using anelectrically conductive formation within a Printed Circuit Board (PCB).The system includes a laminate waveguide structure 393 c having anaperture 393 b, and at least two laminas 390 a, 390 b, 390 c belongingto a PCB. A first electrically conductive surface 361 b is printed onone of the laminas 390 a and located over the aperture 393 b. The firstelectrically conductive surface 361 b has an area at least large enoughto cover most of the aperture 393 b. A plurality of VerticalInterconnect Access (VIA) holes 371 b are filled or plated with anelectrically conductive material, electrically connecting the firstelectrically conductive surface 361 b to the laminate waveguidestructure 393 c, forming an electrically conductive cage 302 c over theaperture 393 b. A millimeter-wave transmitter device 391 is optionallyplaced on one of the laminas 390 a, inside a first cavity 393 e formedin at least one of the laminas 390 b, 390 c, and contained inside theelectrically conductive cage 302 c over the aperture 393 b.

In one embodiment, the system directs millimeter-waves 395, transmittedby the millimeter-wave transmitter device 391 using an integratedradiating element 392, towards the laminate waveguide structure 393 c.

In one embodiment, the laminate waveguide structure includes at leastone additional lamina 390 d, 390 e, 390 f, belonging to the PCB andhaving a second cavity 393 d shaped in the form of the aperture 393 b,and an electrically conductive plating 394 applied on walls of thesecond cavity 393 d. The second cavity 393 d is located below theelectrically conductive cage 302 c, and the electrically conductive cage302 c optionally reaches and electrically connects with the electricallyconductive plating 394 via additional electrically conductive surfaces394 b extending outwards from the electrically conductive plating 394.

In one embodiment, the electrically conductive cage 302 c comprising thefirst electrically conductive surface 361 b prevents energy loss bydirecting millimeter-waves 395 towards the unsealed end of the laminatewaveguide structure 393 c.

FIG. 14 illustrates one embodiment of a system for directingelectromagnetic millimeter-waves towards a waveguide using anelectrically conductive formation within a Printed Circuit Board (PCB).The system includes a waveguide 396 having an aperture 425, and at leasttwo laminas belonging to a PCB 420 a, 420 b, 420 c, 420 d, 420 e, 420 f,420 g. A first electrically conductive surface 421 is printed on one ofthe laminas 420 a and located over the aperture 425, the firstelectrically conductive surface 421 having an area at least large enoughto cover most of the aperture 425. A plurality of Vertical InterconnectAccess (VIA) holes 422 are filled or plated with an electricallyconductive material and electrically connect the first electricallyconductive surface 421 to the waveguide 396, forming an electricallyconductive cage 423 over the aperture 425. A millimeter-wave transmitterdevice 398 is optionally placed on one of the laminas 420 c, inside afirst cavity 424 formed in at least one of the laminas, 420 d, 420 e,420 f, 420 g, and is contained inside the electrically conductive cage423 over the aperture 425. In one embodiment, the system directsmillimeter-waves 399, transmitted by the millimeter-wave transmitterdevice 398 using an integrated radiating element 397, towards thewaveguide 396. In one embodiment, the waveguide 396 is a discretewaveguide attached to the PCB, and electrically connected to theelectrically conductive cage 423. In one embodiment, the area of thefirst electrically conductive surface 421 is large enough tosubstantially cover the aperture of a waveguide.

FIG. 15 illustrates one embodiment of a system for injecting, guiding,and receiving millimeter-waves inside a Printed Circuit Board (PCB). Thesystem includes at least two laminas, illustrated as seven laminas 411,412, 413, 414, 415, 416, 417 by way of example, belonging to a PCB, andtwo electrically conductive surfaces 401, 402 printed on the at leasttwo laminas 411, 417, each electrically conductive surface printed on adifferent lamina. A plurality of Vertical Interconnect Access (VIA)holes 403 are filled or plated with an electrically conductive material,and placed side by side forming a contour of a waveguide aperture 410 b.The VIA holes 403, with the electrically conductive material, passthrough the laminas 411, 412, 413, 414, 415, 416, 417 contained betweenthe two electrically conductive surfaces 401, 402, and electricallyinterconnect the two electrically conductive surfaces 401, 402, forminga waveguide 410 sealed from both ends within the PCB. A transmitterprobe 405 is optionally located within the waveguide 410, and is printedon one of the at least two laminas 411. A receiver probe 406 is locatedwithin the waveguide 410, and is printed on one of the at least twolaminas 417 not carrying the transmitter probe 405.

In one embodiment, the receiver probe 406 configured to receivemillimeter-waves 409 injected to the waveguide 410 by the transmitterprobe 405. In one embodiment, at least two of the laminas 413, 414, 415located between the transmitter probe 405 and the receiver probe 406 arecontiguous, and include a cavity 410 c formed in the at least two of thelaminas 413, 414, 415. An electrically conductive plating 410 d isapplied on the walls of the cavity 410 c. In one embodiment, theelectrically conductive plating 410 d enhances the conductivity of thewaveguide 410.

FIG. 16 illustrates one embodiment of a system for injecting, guiding,and receiving millimeter-waves inside a PCB, similar to the systemillustrated by FIG. 15, with the only difference being that theelectrically conductive cage 410 k does not comprise a cavity. In thiscase, the electrically conductive cage 410 k of the waveguide is formedsolely by VIA holes filled or plated with electrically conductivematerial.

In order to use standard PCB technology in association withmillimeter-wave frequencies, special care is required to assure adequatesignal transition and propagation among various elements. In oneembodiment, a bare-die Integrated Circuit is placed in a specially madecavity within a PCB. The cavity is optionally made as thin as thebare-die Integrated Circuit, such that the upper surface of the bare-dieIntegrated Circuit levels with an edge of the cavity. This arrangementallows wire-bonding or strip-bonding signal and ground contacts on thebare-die Integrated Circuit with pads located on the edge of the cavityand printed on a lamina of the PCB. The wire or strip used for bondingmay be kept very short, because of the tight placement of the bare-dieIntegrated Circuit side-by-side with the edge of the cavity, and due tothe fact that the bare-die Integrated Circuit may level at substantiallythe same height of the cavity edge. Short bonding wires or strips mayfacilitate efficient transport of millimeter-wave signals from thebare-die Integrated Circuit to the pads and vice versa. The pads may bepart of transmission line formations, such as Microstrip or waveguides,used to propagate signals through the PCB into other components andelectrically conductive structures inside and on the PCB.

In one embodiment, a system enabling interface between a millimeter-wavebare-die and a Printed Circuit Board (PCB) includes a cavity of depthequal to X formed in at least one lamina of a PCB. Three electricallyconductive pads are printed on one of the laminas of the PCB, the padssubstantially reach the edge of the cavity. A bare-die IntegratedCircuit or a heightened bare-die Integrated Circuit, optionally having athickness equal to X, is configured to output a millimeter-wave signalfrom three electrically conductive contacts arranged in aground-signal-ground configuration on an upper side edge of the bare-dieIntegrated Circuit. The bare-die Integrated Circuit is placed inside thecavity optionally such that the electrically conductive pads and theupper side edge containing the electrically conductive contacts arearranged side-by-side at substantially the same height. Three bondingwires or strips electrically connect each electrically conductivecontact to one of the electrically conductive pads. In one embodiment,the system transports millimeter-wave signals from the electricallyconductive contacts to the electrically conductive pads across the smalldistance formed between the electrically conductive contacts and theelectrically conductive pads.

FIG. 17A, FIG. 17B, FIG. 17C, and FIG. 17D illustrate one embodiment ofa low-loss interface between a millimeter-wave bare-die IntegratedCircuit 471 or a heightened bare-die Integrated Circuit 471 h and a PCB470. The heightened bare-die Integrated Circuit 471 h may include abare-die Integrated Circuit 471 b mounted on top of a heighteningplatform 479. The heightening platform 479 may be heat conducting, andmay be glued or bonded to the bare-die Integrated Circuit 471 b.Throughout the specification and claims, a bare-die Integrated Circuitis completely interchangeable with a heightened bare-die IntegratedCircuit. A cavity 450 of depth equal to X, is formed in the PCB, in atleast one lamina of the PCB illustrated as two laminas 452 by way ofexample. The depth of the cavity 450 is denoted by numeral 451. Otherembodiments not illustrated may include a cavity inside a single lamina,the cavity being of depth lesser than the single lamina, or a cavitythrough multiple laminas ending inside a lamina. Three electricallyconductive pads 461, 462, 463, are printed on one of the laminas of theBoard, such that the electrically conductive pads 461, 462, 463substantially reach the upper side edge 472 of the cavity 450. Thethickness of the bare-die Integrated Circuit 471 is denoted by numeral451 b. The thickness of the heightened bare-die Integrated Circuit 471 his denoted by numeral 451 h. Optionally, the thickness 451 b of thebare-die Integrated Circuit 471 or the thickness 451 h of the heightenedbare-die Integrated Circuit 471 h is substantially the same as the depth451 of the cavity 450. The bare-die Integrated Circuit is configured totransmit and/or receive millimeter-wave signals from three electricallyconductive contacts 481, 482, 483 arranged in a ground-signal-groundconfiguration on an upper side edge of the bare-die Integrated Circuit471. The bare-die Integrated Circuit 471 is placed inside the cavity 450such that the electrically conductive pads 461, 462, 463 and the upperside edge 472 are arranged side-by-side at substantially the same heightequal to X above the floor of the cavity. Three bonding wires 491, 492,493 or strips are used to electrically connect each electricallyconductive contact 481, 482, 483 to one of the electrically conductivepads 461, 462, 463 respectively. The interface is operative to transporta millimeter-wave signal from the electrically conductive contacts 481,482, 483 to the electrically conductive pads 461, 462, 463 across adistance 499 which is small and formed between the electricallyconductive contacts 481, 482, 483 and the electrically conductive pads461, 462, 463.

In one embodiment, X is between 100 micron and 300 micron. In oneembodiment the distance 499 is smaller than 150 micron. In oneembodiment the distance 499 is smaller than 250 micron. In oneembodiment the distance 499 is smaller than 350 micron. In oneembodiment, at least one additional lamina belonging to the PCB islocated above the at least one lamina in which the cavity 450 of depthequal to X is formed. The at least one additional lamina having a secondcavity above the cavity of depth equal to X, such that the bare-dieIntegrated Circuit 471, the bonding wires 491, 492, 493, and theelectrically conductive pads 461, 462, 463 are not covered by the atleast one additional lamina, and the two cavities form a single cavityspace. Optionally, a sealing layer, placed over the second cavity,environmentally seals the bare-die Integrated Circuit 471, the bondingwires 491, 492, 493, and the electrically conductive pads 461, 462, 463,inside the PCB.

In one embodiment, a plurality of Vertical Interconnect Access (VIA)holes, filled with heat conducting material, reach the floor of thecavity 450 and are thermally coupled to the bottom of the bare-dieIntegrated Circuit or heightening platform. The heat conducting materialmay both thermally conduct heat away from the bare-die IntegratedCircuit into a heat sink coupled to the VIA holes, and maintain a sealedenvironment inside the cavity. In one embodiment, the heat conductingmaterial is operative to maintain a sealed environment inside thecavity. Conducting epoxy, solder or copper is operative to both maintaina sealed environment inside the cavity, and conduct heat.

FIG. 18A and FIG. 18B illustrate one embodiment of sealing a bare-dieIntegrated Circuit 471. At least one additional lamina, illustrated astwo additional laminas 473 by way of example, is located above thelaminas 452 through which the cavity 450 of depth equal to X is formed.The additional laminas 473 have a second cavity 476 above the cavity 450of depth equal to X, such that the bare-die Integrated Circuit 471, thebonding wires 491, 492, 493, and the electrically conductive pads 461,462, 463 are not covered by additional laminas 473, and the cavity 450and the second cavity 476 form a single cavity space 475.

In one embodiment, a sealing layer 474 is placed over the second cavity476, such that the bare-die Integrated Circuit 471, the bonding wires491, 492, 493, and the electrically conductive pads 461, 462, 463 areenvironmentally sealed inside the PCB. The sealing layer 474 may beconstructed from millimeter-wave absorbing material such as ECCOSORB BSRprovided by Emerson & Cuming, in order to prevent spurious oscillations.The sealing layer 474 may be attached to the additional laminas 473using adhesive, or soldered to the additional laminas 473, in order toprovide hermetic seal.

In one embodiment, a plurality of Vertical Interconnect Access holes478, filled with heat conducting material such as epoxy, solder orcopper, reach the floor of cavity 450. The heat conductive fill isthermally coupled to the bottom of the bare-die Integrated Circuit 471or the heightening platform 479. The heat conducting material isoptionally operative to both (i) thermally conduct heat away from thebare-die Integrated Circuit 471 into a heat sink coupled to the holes,and (ii) maintain a sealed environment inside the single cavity space475, protecting a bare-die Integrated Circuit 471 against environmentalelements such as humidity and dust.

In one embodiment, a laminate waveguide structure is embedded in thelaminas of PCB 470. A probe is printed on the same lamina as theelectrically conductive pad 462 connected to the electrically conductivecontact 482 associated with the signal, and located inside the laminatewaveguide structure. A transmission line signal trace is printed as acontinuation to the electrically conductive pad 462 connected to theelectrically conductive contact 482 associated with the signal, thetransmission line signal trace electrically connecting the electricallyconductive contact 482 associated with the signal, to the probe.

In one embodiment, the system guides a signal from the bare-dieIntegrated Circuit 471, through the transmission line signal trace, intothe laminate waveguide structure, and outside of the laminate waveguidestructure.

In one embodiment, additional laminas 473 belonging to the PCB 470 arelocated above laminas 452 in which the cavity 450 of depth equal to X isformed. The additional laminas 473 having a second cavity 476 above thecavity 450 of depth equal to X, such that the bare-die IntegratedCircuit 471 and the bonding wires 491, 492, 493 are not covered by theadditional laminas 473, and the two cavities 450, 476 form a singlecavity space 475. The laminate waveguide structure embedded in thelaminas of the PCB 470 includes a third cavity optionally having anelectrically conductive plating, in at least some of the laminas of thePCB 470, and optionally a first electrically conductive surface printedon one of the additional laminas 473. Optionally, the first electricallyconductive surface seals the laminate waveguide structure from one endusing an electrically conductive cage comprising VIA holes, inaccordance with some embodiments.

In one embodiment, two electrically conductive pads connected to theelectrically conductive contacts 481, 483 associated with the ground,are electrically connected, using electrically conductive VIAstructures, to a ground layer below the electrically conductive pads,wherein the ground layer together with the transmission line signaltrace form a Microstrip transmission line.

In one embodiment, two electrically conductive pads connected to theelectrically conductive contacts 481, 483 associated with the ground,are continued as two electrically conductive traces alongside thetransmission line signal trace, forming a Co-planar transmission linetogether with the transmission line signal trace.

FIG. 19A and FIG. 19B illustrate two embodiments of a bare-dieIntegrated Circuit 471 t, 471 u, similar to bare-die Integrated Circuit471, electrically connected to a transmission line signal trace 572, 572u. In one embodiment, the electrically conductive pads 461 t, 463 tconfigured as ground are connected, using electrically conductive VIAstructures 572 t, to a ground layer 571 printed under the transmissionline signal trace 572. The ground layer 571 together with thetransmission line signal trace 572 form a Microstrip transmission line.In one embodiment, electrically conductive pads 575 g, 576 g configuredas ground are continued as two electrically conductive traces 575, 576alongside the transmission line signal trace 572 u, forming a Co-planartransmission line together with the transmission line signal trace 572u.

In one embodiment, the same lamina used to carry the probe andtransmission line signal trace 572 on one side, is the lamina used tocarry the ground layer 571 on the opposite side, and is made out of asoft laminate material suitable to be used as a millimeter-wave bandsubstrate in PCB, such as Rogers® 4350B, Arlon CLTE-XT, or Arlon AD255A.

FIG. 20 illustrates one embodiment of a bare-die Integrated Circuitelectrically connected to a transmission line reaching a printed probeinside a laminate waveguide structure. A transmission line 501electrically connects an electrically conductive pad 501 b to a probe502; wherein the electrically conductive pad 501 b is associated with anelectrically conductive contact through which a millimeter-wave signalis received or transmitted, such as electrically conductive contact 482belonging to a bare-die Integrated Circuit such as bare-die IntegratedCircuit 471. A probe 502 is located inside a laminate waveguidestructure 507 embedded within a PCB, in accordance with someembodiments. A millimeter-wave signal generated by bare-die IntegratedCircuit 509 similar to bare-die Integrated Circuit 471 is injected intothe transmission line 501 via bonding wires, propagates up to the probe502, radiated by the probe 502 inside the laminate waveguide structure507 as a millimeter-wave 505, and is then guided by the laminatewaveguide structure 507 out of the PCB. The millimeter-wave signal pathmay be bi-directional, and optionally allows millimeter-wave signals tobe picked-up by the bare-die Integrated Circuit 509. The bare-dieIntegrated Circuit 509 is placed in a cavity formed in the PCB, inaccordance with some embodiments. The depth 508 of a second cavity 508 bformed above the cavity in which the bare-die Integrated Circuit 509 isplaced, can be designed such as to form a desired distance 508 betweenthe probe 502 and a first electrically conductive surface 500 a used toelectromagnetically seal the laminate waveguide formation 507 at oneend.

In one embodiment, at least one additional lamina illustrated as twoadditional laminas 508 c by way of example, belonging to the PCB, islocated above laminas 508 d in which cavity 508 e of depth equal to X isformed. The additional laminas 508 c having a second cavity 508 b abovecavity 508 e, such that the bare-die Integrated Circuit 509 and thebonding wires are not covered by the additional laminas 508 c, and thetwo cavities 508 e, 508 b form a single cavity space 508 f, inaccordance with some embodiments. The laminate waveguide structure 507embedded in the laminas of the PCB includes a third cavity 508 foptionally having an electrically conductive plating 500 b, in at leastsome of the laminas of the PCB, and optionally a first electricallyconductive surface 500 a printed on one of the additional laminas 508 c.Optionally, the first electrically conductive surface 500 a seals thelaminate waveguide structure 507 from one end using an electricallyconductive cage comprising VIA holes 500 c, in accordance with someembodiments.

In one embodiment, the aperture of the laminate waveguide structure 507is dimensioned to result in a laminate waveguide structure 507 having acutoff frequency above 20 GHz. In one embodiment, the aperture oflaminate waveguide structure 507 is dimensioned to result in a laminatewaveguide structure 507 having a cutoff frequency above 50 GHz. In oneembodiment, the aperture of laminate waveguide structure 507 isdimensioned to result in a laminate waveguide structure 507 having acutoff frequency above 57 GHz.

In one embodiment, a discrete waveguide is attached to the PCB 470. Aprobe printed on the same lamina as the electrically conductive pad 462connected to the electrically conductive contact 482 associated with thesignal, and located below the aperture of the discrete waveguide. Atransmission line signal trace printed as a continuation to theelectrically conductive pad 462 connected to the electrically conductivecontact 482 associated with the signal, the transmission line signaltrace electrically connecting the electrically conductive contact 482associated with the signal to the probe.

In one embodiment, the system guides a signal from the bare-dieIntegrated Circuit 471, through the transmission line signal trace, intothe discrete waveguide, and outside of the discrete waveguide.

In one embodiment, additional laminas 473 belonging to the PCB 470 arelocated above laminas 452 in which the cavity 450 of depth equal to X isformed, and carries the discrete waveguide. The additional laminas 473have a second cavity 476 above the cavity 450 of depth equal to X, suchthat the bare-die Integrated Circuit 471, the bonding wires 491, 492,493, and the electrically conductive pads 461, 462, 463 are not coveredby the additional laminas 473, and the two cavities 450, 476 form asingle cavity space 475. A first electrically conductive surface printedon a lamina located below the probe seals the discrete waveguide fromone end using an electrically conductive cage comprising VIA holes.

FIG. 22 illustrates one embodiment of a bare-die Integrated Circuit IC,electrically connected to a transmission line signal trace ending with aprobe located inside an electrically conductive cage configured to sealone end of a discrete waveguide, in accordance with some embodiments. Abare-die Integrated Circuit 542 is placed inside a cavity in a PCB, andis connected with a transmission line signal trace 543 b using bondingwire or strip, in accordance with some embodiments. A discrete waveguide541 is attached to the PCB. A probe 543 is printed at one end of thetransmission line signal trace 543 b, and located below the aperture ofthe discrete waveguide 541. A first electrically conductive surface 545is printed on a lamina located below the probe 543, sealing the discretewaveguide from one end using an electrically conductive cage comprisingVIA holes filled with eclectically conductive material, in accordancewith some embodiments. Optionally, a millimeter-wave signal istransported by the transmission line signal trace 543 b from thebare-die Integrated Circuit 542 to the probe 543, and is radiated asmillimeter-waves 547 through the discrete waveguide 541.

In one embodiment, a probe is printed in continuation to theelectrically conductive pad 462 connected to the electrically conductivecontact 482 associated with the signal. A discrete waveguide is attachedto the PCB 470, such that the bare-die Integrated Circuit 471 and theprobe are located below the aperture of the discrete waveguide. In oneembodiment, the system is configured to guide a signal from the bare-dieIntegrated Circuit 471, through the probe, into the discrete waveguide,and outside of the discrete waveguide.

In one embodiment, a first electrically conductive surface printed on alamina located below the probe and bare-bare-die Integrated Circuit 471,seal the discrete waveguide from one end using an electricallyconductive cage comprising VIA holes, such that the probe andbare-bare-die Integrated Circuit 471 are located inside the electricallyconductive cage.

FIG. 23 illustrates one embodiment of a bare-die Integrated Circuit 559,electrically connected to a probe 551, both located inside anelectrically conductive cage 553 that seals one end of a discretewaveguide 541 b. A bare-die Integrated Circuit 559 is placed inside acavity in a PCB, and is connected with a probe 551 using a bonding wireor strip, in accordance with some embodiments. A discrete waveguide 541b is attached to the PCB. The probe 551 is located below the aperture ofthe discrete waveguide 541 b. A first electrically conductive surface552 is printed on a lamina located below the probe 551, sealing thediscrete waveguide 541 b from one end using an electrically conductivecage 553 comprising VIA holes 554 filled with electrically conductivematerial, in accordance with some embodiments. Both the bare-dieIntegrated Circuit 559 and the probe 551 are located inside theelectrically conductive cage 553. Optionally, a millimeter-wave signalis delivered to the probe 551 directly from the bare-die IntegratedCircuit 559, and is radiated from there through the discrete waveguide.

In one embodiment, a system for interfacing between a millimeter-waveflip-chip and a laminate waveguide structure embedded inside a PrintedCircuit Board (PCB) includes a cavity formed in a PCB, going through atleast one lamina of the PCB. An electrically conductive pad inside thecavity is printed on a lamina under the cavity, wherein the lamina underthe cavity forms a floor to the cavity. A flip-chip Integrated Circuitor a Solder-Bumped die is configured to output a millimeter-wave signalfrom a bump electrically connected with the electrically conductive pad.A laminate waveguide structure is embedded in laminas of the PCB,comprising a first electrically conductive surface printed on a laminaof the PCB above the floor of the cavity. A probe is optionally printedon the same lamina as the electrically conductive pad, and is locatedinside the laminate waveguide structure and under the first electricallyconductive surface. A transmission line signal trace is printed as acontinuation to the electrically conductive pad, the transmission lineelectrically connecting the bump associated with the signal to theprobe.

In one embodiment, the system guides a signal from the flip-chip orSolder-Bumped die, through the transmission line signal trace, into thelaminate waveguide structure, and outside of the laminate waveguidestructure. In one embodiment, the laminate waveguide structure embeddedin the laminas of the PCB includes a second cavity, plated withelectrically conductive plating, in at least some of the laminas of thePCB, and the first electrically conductive surface printed above thesecond cavity seals the laminate waveguide structure from one end usingan electrically conductive cage comprising VIA holes.

FIG. 21 illustrates one embodiment of a flip-chip Integrated Circuit, orSolder-Bumped die 521, electrically connected to a transmission linesignal trace 523 reaching a probe 525 inside a laminate waveguidestructure 529. A cavity 528 is formed in a PCB, going through at leastone lamina of the PCB. An electrically conductive pad 522 b is printedon a lamina 528 b comprising the floor of the cavity 528 c. A flip-chipIntegrated Circuit, or Solder-Bumped die, 521, placed inside cavity 528,is configured to output a millimeter-wave signal from a bump 522electrically connected to the electrically conductive pad 522 b. Alaminate waveguide structure 529, in accordance with some embodiments,is embedded in the PCB. A probe 525 is printed on the same lamina 528 bas the electrically conductive pad 522 b, and located inside thelaminate waveguide structure 529, under a first electrically conductivesurface 526 printed above lamina 528 b. A transmission line signal trace523, printed as a continuation to the electrically conductive pad 522 b,is electrically connecting the bump to the probe 525. The system isconfigured to guide a signal from the flip-chip Integrated Circuit, 521through the transmission line signal trace 523, into the laminatewaveguide structure 529, and outside of the laminate waveguide structure529 in the form of millimeter-waves 527. The depth of the cavity 528 canbe designed such as to form a desired distance between the probe 525 anda first electrically conducive surface 526 used to electromagneticallyseal the laminate waveguide structure at one end. In one embodiment, theflip-chip Integrated Circuit, or Solder-Bumped die, is sealed inside thecavity 528, in accordance with some embodiments.

In one embodiment, the laminate waveguide structure 529 embedded in thelaminas of the PCB includes a second cavity 529 b, plated withelectrically conductive plating 526 c, in at least some of the laminasof the PCB, and the first electrically conductive surface 526 printedabove the second cavity 529 b seals the laminate waveguide structure 529from one end using an electrically conductive cage 526 a comprising VIAholes 526 b.

In one embodiment, a system enabling interface between a millimeter-wavebare-die Integrated Circuit and a Printed Circuit Board (PCB) includes acavity of depth equal to X formed in at least one lamina of a PCB. Twoelectrically conductive pads are printed on one of the laminas of thePCB, the electrically conductive pads reach the edge of the cavity. Abare-die Integrated Circuit of thickness equal to X, or a heightenedbare-die Integrated Circuit of thickness equal to X, is configured tooutput a millimeter-wave signal from two electrically conductivecontacts arranged in differential signal configuration on an upper sideedge of the bare-die Integrated Circuit; the bare-die Integrated Circuitis placed inside the cavity such that the electrically conductive padsand the upper side edge containing the electrically conductive contactsare arranged side-by-side at substantially the same height. Two bondingwires or strips electrically connect each electrically conductivecontact to a corresponding electrically conductive pad.

In one embodiment, the system transports millimeter-wave signals fromthe electrically conductive contacts to the electrically conductive padsacross the small distance formed between the electrically conductivecontacts and the electrically conductive pads.

In one embodiment, a laminate waveguide structure is embedded in thelaminas of the PCB. A probe is printed on the same lamina as theelectrically conductive pads, and located inside the laminate waveguidestructure. A co-planar or slot-line transmission line printed as acontinuation to the electrically conductive pads, the co-planar orslot-line transmission line electrically connecting the electricallyconductive pads to the probe.

In one embodiment, the system guides a signal from the bare-dieIntegrated Circuit, through the co-planar or slot-line transmissionline, into the laminate waveguide structure, and outside of the laminatewaveguide structure.

In one embodiment, a discrete waveguide is attached to the PCB. A probeis printed on the same lamina as the electrically conductive pads, andlocated below the aperture of the discrete waveguide. A co-planar orslot-line transmission line is printed as a continuation to theelectrically conductive pads, the co-planar or slot-line transmissionline electrically connecting the electrically conductive pads to theprobe.

In one embodiment, the system guides a signal from the bare-dieIntegrated Circuit, through the co-planar or slot-line transmissionline, into the discrete waveguide, and outside of the discretewaveguide.

FIG. 19C illustrates one embodiments of a bare-die Integrated Circuit471 v or a heightened bare-die Integrated Circuit electrically connectedto a co-planar or slot-line transmission line 575 d, 576 d. The bare-dieIntegrated Circuit 471 v of thickness equal to X is placed in a cavityof depth equal to X, in accordance with some embodiments. Two bondingwires 489 a, 489 b are used to electrically connect electricallyconductive contacts 479 a, 479 b, arranged in differential signalconfiguration on the bare-die Integrated Circuit, to two electricallyconductive pads 499 a, 499 b, extending into the co-planar or slot-linetransmission line 575 d, 576 d transmission line. In one embodiment, thetransmission line reaches a probe 575 p. In one embodiment, the probe islocated either above a laminate waveguide structure formed within thePCB, or below a discrete waveguide attached to the PCB, in accordancewith some embodiments.

In one embodiment, a bare-die Integrated Circuit implemented in SiGe(silicon-germanium) or CMOS, typically has electrically conductivecontacts placed on the top side of the bare-die Integrated Circuit. Theelectrically conductive contacts are optionally arranged in a tightpitch configuration, resulting in small distances between oneelectrically conductive contact center point to a neighboringelectrically conductive contact center point. According to one example,a 150 micron pitch is used. The electrically conductive contacts areconnected with electrically conductive pads on the PCB via bonding wiresor strips. The bonding wires or strips have a characteristic impedancetypically higher than the impedance of the bare-die Integrated Circuitused to drive or load the bonding wires. According to one example, thebonding wires have a characteristic impedance between 75 and 160 ohm,and a single ended bare-die Integrated Circuit has an impedance of 50ohm used to drive or load the bonding wires. In one embodiment, a narrowtransmission line signal trace printed on the PCB is used to transport amillimeter-wave signal away from the electrically conductive pads. Inone embodiment, the narrow transmission line signal trace is narrowenough to fit between two electrically conductive pads of ground,closely placed alongside corresponding electrically conductive contactsof ground on the bare-die Integrated Circuit. According to one example,the thin transmission line signal trace has a width of 75 microns, whichallows a clearance of about 75 microns to each direction whereelectrically conductive pads of ground are found, assuming aground-signal-ground configuration at an electrically conductive contactpitch (and corresponding electrically conductive pad pitch) of 150microns. In one embodiment, the thin transmission line signal traceresults in a characteristic impedance higher than the impedance of thebare-die Integrated Circuit used to drive or load the bonding wires, andtypically in the range of 75-160 ohm. In one embodiment, a long-enoughthin transmission line signal trace, together with the bonding wires orstrips, creates an impedance match for the bare-die Integrated Circuitimpedance used to drive or load the bonding wires. In this case, thelength of the thin transmission line signal trace is calculated toresult in said match. In one embodiment, after a certain length, thethin transmission line signal trace widens to a standard transmissionline width, having standard characteristic impedance similar to thebare-die Integrated Circuit impedance used to drive or load the bondingwires, and typically 50 ohm.

In one embodiment, a system for matching impedances of a bare-dieIntegrated Circuit and bonding wires includes a bare-die IntegratedCircuit or a heightened bare-die Integrated Circuit configured to outputor input, at an impedance of Z3, a millimeter-wave signal from threeelectrically conductive contacts arranged in a ground-signal-groundconfiguration on an upper side edge of the bare-die Integrated Circuit.Optionally, the spacing between the center point of the electricallyconductive contact associated with the signal to each of the centerpoints of the electrically conductive contact associated with the groundis between 100 and 250 microns. Three electrically conductive pads areprinted on one of the laminas of a Printed Circuit Board (PCB), arrangedin a ground-signal-ground configuration alongside the upper side edge ofthe bare-die Integrated Circuit, and connected to the three electricallyconductive contacts via three bonding wires respectively, the bondingwires have a characteristic impedance of Z1, wherein Z1>Z3. Theelectrically conductive pad associated with the signal extends to form atransmission line signal trace of length L, the transmission line signaltrace has a first width resulting in characteristic impedance of Z2,wherein Z2>Z3. Optionally, the transmission line signal trace widens toa second width, higher than the first width, after the length of L,operative to decrease the characteristic impedance of the transmissionline signal trace to substantially Z3 after the length L and onwards,where Z3 is at most 70% of Z2 and Z3 is at most 70% of Z1. In oneembodiment, the system is configured to match an impedance seen by thebare-die Integrated Circuit at the electrically conductive contacts withthe impedance Z3, by determining L.

FIG. 24A illustrates one embodiment of a system configured to matchdriving or loading impedances of a bare-die Integrated Circuit andbonding wires. A bare-die Integrated Circuit 631 is configured to outputor input at an impedance of Z3, a millimeter-wave signal from threeelectrically conductive contacts 633, 634, 635 arranged in aground-signal-ground configuration on an upper side edge of the bare-dieIntegrated Circuit. The spacings 621, 622 between the center point ofthe electrically conductive contact 634 to each of the center points ofthe electrically conductive contacts 633, 635 is between 100 and 250microns. Three electrically conductive pads 637, 638, 639 are printed onone of the laminas of a PCB. The electrically conductive pads arearranged in a ground-signal-ground configuration alongside theelectrically conductive contacts 633, 634, 635, or in proximity to theelectrically conductive contacts. The electrically conductive pads 637,638, 639 are connected to the three electrically conductive contacts633, 634, 635 via three short bonding wires 641, 642, 643 respectively.The bonding wires 641, 642, 643 have a characteristic impedance ofZ1>Z3. Electrically conductive pad 638 extends to form a transmissionline signal trace 638 b of length L, the length is denoted by numeral629, while the width of the transmission line signal trace, denoted bynumeral 627, is designed to result in a characteristic impedance of Z2,wherein Z2>Z3. The transmission line signal trace widens, to a new widthdenoted by numeral 628, after the length of L. The transmission linesignal trace has a characteristic impedance of substantially Z3 afterthe length L and onwards. In one embodiment, Z3 is at most 70% of Z2 andZ3 is at most 70% of Z1. Optionally, the system matches an impedanceseen by the bare-die Integrated Circuit at the electrically conductivecontacts with the impedance Z3, by determining L. There exists at leastone value of L, for which the system matches an impedance seen by thebare-die Integrated Circuit at the electrically conductive contacts withthe impedance Z3, by determining L, therefore, optionally, allowing fora maximal power transfer between the bare-die Integrated Circuit and thebonding wires. In one embodiment, the length L is determined such thatthe cumulative electrical length, up to the point where the transmissionline signal trace 638 b widens, is substantially one half the wavelengthof the millimeter-wave signal transmitted via the electricallyconductive contact 634 associated with the signal.

In one embodiment, a cavity of depth equal to X is formed in the PCB,going through at least one lamina of the PCB, wherein the threeelectrically conductive pads 637, 638, 639 are printed on one of thelaminas of the PCB, and the electrically conductive pads 637, 638, 639substantially reach the edge of the cavity. The bare-die IntegratedCircuit or the heightened bare-die Integrated Circuit 631 is ofthickness equal to X, and the bare-die Integrated Circuit or theheightened bare-die Integrated Circuit 631 is placed inside the cavitysuch that the electrically conductive pads 637, 638, 639 and theelectrically conductive contacts 633, 634, 635 are arranged side-by-sideat substantially the same height, in accordance with some embodiments.Optionally, the system transports millimeter-wave signals between theelectrically conductive contacts 633, 634, 635 and the electricallyconductive pads 637, 638, 639 across a small distance of less than 500microns, formed between each electrically conductive contact 633, 634,635 and corresponding electrically conductive pad 637, 638, 639.

In one embodiment, the two electrically conductive pads 637, 639connected to the electrically conductive contacts 633, 635 associatedwith the ground are electrically connected, through VerticalInterconnect Access holes, to a ground layer below the electricallyconductive pads 637, 639, wherein the ground layer together with thetransmission line signal trace 638 b form a Microstrip transmissionline, in accordance with some embodiments.

In one embodiment, the two electrically conductive pads 637, 639connected to the electrically conductive contacts 633, 635 associatedwith the ground are electrically connected, using capacitive padextensions, to a ground layer below the electrically conductive pads637, 639, wherein the ground layer together with the transmission linesignal trace form a Microstrip transmission line. Optionally, thecapacitive pad extensions are radial stubs.

In one embodiment, the same lamina used to carry transmission linesignal trace 638 b and electrically conductive pads 637, 638, 639 on oneside, is the lamina used to carry the ground layer on the opposite side,and the lamina used to carry transmission line signal trace 638 b ismade out of a soft laminate material suitable to be used as amillimeter-wave band substrate in PCB, such as Rogers® 4350B, ArlonCLTE-XT, or Arlon AD255A.

In one embodiment, Z1 is between 75 and 160 ohm, Z2 is between 75 and160 ohm, and Z3 is substantially 50 ohm. In one embodiment, the spacings621, 622 between the center point of electrically conductive contact 634associated with the signal to each of the center points of electricallyconductive contacts 633, 635 associated with the grounds, issubstantially 150 microns, the width 627 of transmission line signaltrace 638 b up to length L is between 65 and 85 microns, and the spacingbetween the transmission line signal trace 638 b and each ofelectrically conductive pads 637, 639 associated with the ground isbetween 65 and 85 microns.

In one embodiment, a transmission line signal trace 638 b has acharacteristic impedance Z2 between 75 and 160 ohm and length L between0.5 and 2 millimeters, is used to compensate a mismatch introduced bybonding wires 641, 642, 643 that have a characteristic impedance Z1between 75 and 160 ohm and a length between 200 and 500 microns.

FIG. 24B illustrates one embodiment of using a Smith chart 650 todetermine the length L. Location 651, illustrated as a first X on theSmith chart represents impedance Z3, at which the bare-die IntegratedCircuit inputs or outputs millimeter-wave signals. Location 652,illustrated as a second X on the Smith chart represents a first shift inload seen by the bare-die Integrated Circuit, as a result of introducingthe bonding wires 641, 642, 643. Path 659, connecting location 652 backto location 651 in a clockwise motion, represents a second shift in loadseen by the bare-die Integrated Circuit, as a result of introducing thetransmission line signal trace of length L. In one embodiment, L isdefined as the length of a transmission line signal trace needed tocreate the Smith chart motion from location 652 back to location 651,which represents a match to impedance Z3, and cancelation of a mismatchintroduced by the bonding wires. In one embodiment, location 651represents 50 ohm.

In one embodiment, the system is operative to transport themillimeter-wave signal belonging to a frequency band between 20 GHz and100 GHz, from electrically conductive contact 634 associated with thesignal to the transmission line signal trace 638 b. In one embodiment, acapacitive thickening along the transmission line signal trace 638 b,and before the transmission line signal trace 638 b widens, is added inorder to reduce the length L needed to match the impedance seen by thebare-die Integrated Circuit 631 at the electrically conductive contacts633, 634, 635 with the impedance Z3.

FIG. 25 illustrates one embodiment of a system configured to matchdriving or loading impedances of a bare-die Integrated Circuit andbonding wires, in accordance with some embodiments, with the exceptionthat a capacitive thickening 642 of the transmission line signal traceis added, in order to reduce the length L, denoted by numeral 641,needed to match an impedance, seen by a bare-die Integrated Circuit atelectrically conductive contacts of the bare-die Integrated Circuit,with the impedance Z3 in accordance with some embodiments. All thingsotherwise equal, the length 641 is shorter than the length 629 of FIG.24, because of the capacitive thickening 642.

In one embodiment, a system configured to match impedances of a bare-dieIntegrated Circuit and bonding wires includes a bare-die IntegratedCircuit or a heightened bare-die Integrated Circuit configured to outputor input, at an impedance Z3, a millimeter-wave signal from twoelectrically conductive contacts arranged in a side-by-side differentialsignal configuration on an upper side edge of the bare-die IntegratedCircuit. Two electrically conductive pads, printed on one of the laminasof a Printed Circuit Board (PCB), are arranged alongside the upper sideedge of the bare-die Integrated Circuit, and connected to the twoelectrically conductive contacts via two bonding wires respectively, thewires have a characteristic impedance of Z1, wherein Z1>Z3. The twoelectrically conductive pads extend to form a slot-line transmissionline of length L, having a characteristic impedance of Z2, whereinZ2>Z3. Optionally, the slot-line transmission line is configured tointerface with a second transmission line having a characteristicimpedance seen by the slot-line transmission line as substantially Z3.In one embodiment, the system is configured to match an impedance seenby the bare-die Integrated Circuit at the electrically conductivecontacts with the impedance Z3, by determining L.

In one embodiment, a cavity of depth equal to X is formed in the PCB,going through at least one lamina of the PCB. The two electricallyconductive pads are printed on one of the laminas of the PCB, theelectrically conductive pads substantially reach the edge of the cavity.The bare-die Integrated Circuit or the heightened bare-die IntegratedCircuit is optionally of thickness equal to X, and the bare-dieIntegrated Circuit is placed inside the cavity such that theelectrically conductive pads and the upper side edge that contains theelectrically conductive contacts are arranged side-by-side atsubstantially the same height.

In one embodiment, the system is configured to transport millimeter-wavesignals from the electrically conductive contacts to the electricallyconductive pads across a small distance of less than 500 microns, formedbetween each electrically conductive contact and correspondingelectrically conductive pad. In one embodiment, the lamina used to carrythe slot-line transmission line is made out of a soft laminate materialsuitable to be used as a millimeter-wave band substrate in PCB, such asRogers® 4350B, Rogers RT6010, Arlon CLTE-XT, or Arlon AD255A. In oneembodiment, the system transports millimeter-wave signals belonging to afrequency band between 20 GHz and 100 GHz, from the electricallyconductive contacts to the slot-line transmission line. In oneembodiment, Z1 is between 120 and 260 ohm, Z2 is between 120 and 260ohm, and Z3 is substantially two times 50 ohm. In one embodiment, thelength L is determined such that the cumulative electrical length, up tothe end of the slot-line transmission line, is substantially one halfthe wavelength of the millimeter-wave signal transmitted via theelectrically conductive contacts. In one embodiment, the secondtransmission line is a Microstrip, and the interface comprisesbalanced-to-unbalanced signal conversion. In one embodiment, Z1 isbetween 120 and 260 ohm, Z2 is between 120 and 260 ohm, Z3 issubstantially two times 50 ohm, and the Microstrip has a characteristicimpedance of substantially 50 ohm.

FIG. 26 illustrates one embodiment of a system configured to matchimpedances of a bare-die Integrated Circuit and bonding wires. Abare-die Integrated Circuit 631 d is configured to output or input at adifferential port impedance Z3, a millimeter-wave signal from twoelectrically conductive contacts 678, 679 arranged in a side-by-sidedifferential signal port configuration on an upper side edge of thebare-die Integrated Circuit 631 d. Two electrically conductive pads 685,686 are printed on one of the laminas of a PCB. The electricallyconductive pads 685, 686 are arranged alongside the electricallyconductive contacts 678, 679, or in proximity to the electricallyconductive contacts, and connected to the two electrically conductivecontacts via two bonding wires 681, 682 respectively. The bonding wireshave a characteristic impedance of Z1, wherein Z1>Z3. The twoelectrically conductive pads 685, 686 extend to form a slot-linetransmission line 685, 686 of length L 675. The slot-line transmissionline 685, 686 has a characteristic impedance of Z2, wherein Z2>Z3. Theslot-line transmission line 685, 686 is configured to interface with asecond transmission line 689 having a characteristic impedance seen bythe slot-line transmission line 685, 686 as substantially Z3. The systemis configured to match an impedance seen by the bare-die IntegratedCircuit 631 d at the electrically conductive contacts 678, 679 with theimpedance Z3, by determining L.

In one embodiment, a PCB comprising a waveguide embedded within alaminate structure of the PCB, in accordance with some embodiments, isconstructed by first creating a pressed laminate structure comprising acavity belonging to a waveguide. The pressed laminate structure is thenpressed again together with additional laminas to form a PCB. Theadditional laminas comprise additional elements such as a probe printedand positioned above the cavity, and/or a bare-die Integrated Circuitplaced in a second cavity within the additional laminas.

In one embodiment, a method for constructing millimeter-wave laminatestructures using Printed Circuit Board (PCB) processes includes thefollowing steps: Creating a first pressed laminate structure comprisingat least two laminas and a cavity, the cavity is shaped as an apertureof a waveguide, and goes perpendicularly through all laminas of thelaminate structure. Plating the cavity with electrically conductiveplating, using a PCB plating process. Pressing the first pressedlaminate structure together with at least two additional laminascomprising a probe printed on one of the at least two additionallaminas, into a PCB comprising the first pressed laminate structure andthe additional laminas, such that the cavity is sealed only from one endby the additional laminas and the probe, and the probe is positionedabove the cavity.

FIG. 27A, FIG. 27B, FIG. 27C, and FIG. 27D illustrate one embodiment ofa method for constructing a millimeter-wave laminate structure using PCBprocesses. A first pressed laminate structure 702 comprising at leasttwo laminas, illustrated as three laminas 705, 706 707 by way ofexample, and a cavity 703 is created. The cavity is plated with anelectrically conductive plating 704, using a PCB plating process. Thecavity 703 is operative to guide millimeter waves, in accordance withsome embodiments. The first pressed laminate structure 702 is pressed,again, together with at least two additional laminas 709, 710 comprisinga probe 712, into a PCB 715 comprising the first pressed laminatestructure 702 and the additional laminas 709, 710, such that the cavity703 is sealed only from one end by the additional laminas 709, 710, andthe probe 712 is positioned above the cavity 703 and operative totransmit millimeter-waves through the cavity.

In one embodiment, holes 718, 719 are drilled in the additional laminas709, 710, the holes 718, 719 operative to form a second cavity 720 a. Itis noted that the second cavity 720 a is illustrated as being sealed,but cavity 720 a may also be open if hole 718 is made through all oflamina 709. A bare-die Integrated Circuit is placed inside the secondcavity 720 a. An electrically conductive contact on the bare-dieIntegrated Circuit is wire-bonded with a transmission line signal trace712 d printed on one of the additional laminas 709 that carries theprobe 712, the transmission line signal trace 712 d operative to connectwith the probe 712 and transport a millimeter-wave signal from thebare-die Integrated Circuit to the probe 712, and into the cavity 703.It is noted that “drilling holes” in the specifications and claims mayrefer to using a drill to form the holes, may refer to using a cuttingblade to form the holes, or may refer to any other hole-forming action.

FIG. 27B, FIG. 27C, FIG. 27D, FIG. 27E, FIG. 27F, and FIG. 27Gillustrate one embodiment of a method for interfacing a laminatestructure with a bare-die Integrated Circuit. Holes 718, 719 are drilledin the additional laminas 709, 710. The holes 718, 719 form a secondcavity 720 b. It is noted that hole 718 is illustrated as beingpartially made through lamina 709, but it may also be made fully throughlamina 718, such that cavity 720 b is formed unsealed. A bare-dieIntegrated Circuit 725 is placed inside the second cavity 720 b. Bondingwire 727 b is then used to connect an electrically conductive contact728 a on the bare-die Integrated Circuit 725 with a transmission linesignal trace 712 d printed on one of the additional laminas 709 thatcarries the printed probe 712, in accordance with some embodiments. Thetransmission line signal trace 712 d is operative to connect with theprobe 712 and transport a millimeter-wave signal from the bare-dieIntegrated Circuit 725 to the probe 712, and into the cavity 703, inaccordance with some embodiments. It is noted that numeral 712 d denotesa transmission line signal trace which may be printed in continuation toa portion 712 b′ of electrically conductive pad 712 b. Therefore,bonding wire 727 b may be interchangeably describe as either beingconnected to the transmission line signal trace 712 d or to the portion712 b′ of electrically conductive pad 712 b.

In one embodiment, the holes 718, 719 in the additional laminas 709, 710are drilled prior to the step of pressing the first laminate structure702 together with the additional laminas 709, 710, and the holes 718,719 operative to form the second cavity 720 b after the step of pressingthe first laminate structure 702 together with the additional laminas709, 710. In one embodiment, the holes in the additional laminas 709,710 are drilled such that the second cavity 720 a is sealed inside thePCB 715 after the step of pressing the first laminate structure togetherwith the additional laminas 709, 710. In one embodiment, an additionalhole is drilled. The additional hole is operative to open the secondcavity 720 a when sealed. The second cavity 720 b may house the bare-dieIntegrated Circuit 725 after being opened, wherein the second cavity 720a is operative to stay clear of dirt accumulation prior to being opened.

In one embodiment, holes 718, 719 in the additional laminas 709, 710 aredrilled such that a second cavity 720 a is sealed inside the PCB 715after the step of pressing the first laminate structure 702 togetherwith the additional laminas 709, 710. This may be achieved by drillinghole 718 partially through lamina 709. In one embodiment, an additionalhole is drilled. The additional hole is operative to open the secondcavity 720 a into a second cavity 720 b. It is noted that although bothnumerals 720 a and 720 b denote a second cavity, numeral 720 a denotesthe second cavity in a sealed state, and numeral 702 b denotes thesecond cavity in an open state. The second cavity 720 b is operative tohouse the bare-die Integrated Circuit 725, while the second cavity 720 ais operative to stay clear of dirt accumulation prior to bare-dieIntegrated Circuit 725 placement. Dirt accumulation may result fromvarious manufacturing processes occurring between the step of pressingthe laminate structure 702 together with laminas 709, 710, and the stepof opening the second cavity 720 a.

In one embodiment, lamina 709 used to carry the probe 712 on one side,is the same lamina used to carry a ground layer on the opposite side,and is made out of a soft laminate material suitable to be used as amillimeter-wave substrate in PCB, such as Rogers® 4350B, Arlon CLTE-XT,or Arlon AD255A. In one embodiment, the cavity 703 is dimensioned as anaperture of waveguide configured to have a cutoff frequency of 20 GHz,in accordance with some embodiments.

In one embodiment, a method for interfacing a millimeter-wave bare-dieIntegrated Circuit with a PCB comprises: (i) printing an electricallyconductive pad on a lamina of a PCB, (ii) forming a cavity in the PCB,using a cutting tool that also cuts through the electrically conductivepads during the cavity-cutting instance, leaving a portion of theelectrically conductive pad that exactly reaches the edge of the cavity,(iii) placing a bare-die Integrated Circuit inside the cavity, such thatan electrically conductive contact present on an upper edge of thebare-die Integrated Circuit is brought substantially as close aspossible to the portion of the electrically conductive pad, and (iv)wire-bonding the portion of the electrically conductive pad to theelectrically conductive contact using a very short bonding wire requiredto bridge the very small distance formed between the portion of theelectrically conductive pad and the electrically conductive contact.

In one embodiment, the upper edge of the bare-die Integrated Circuitsubstantially reaches the height of the portion of the electricallyconductive pad, in accordance with some embodiments, resulting is a veryshort bonding wire, typically 250 microns in length. The very shortbonding wire facilitates low-loss transport of millimeter-wave signalsfrom the bare-die Integrated Circuit to the portion of the electricallyconductive pad, and to transmission lines signal traces typicallyconnected to the portion of the electrically conductive pad.

In one embodiment, a method for interfacing a bare-die IntegratedCircuit with a Printed Circuit Board (PCB) includes the following steps:Printing electrically conductive pads on one lamina of a PCB. Forming acavity of depth equal to X in the PCB, going through at least one laminaof the PCB; the act of forming the cavity also cuts through theelectrically conductive pads, such that portions of the electricallyconductive pads, still remaining on the PCB, reach an edge of thecavity. Placing a bare-die Integrated Circuit of thickness substantiallyequal to X or a heightened bare-die Integrated Circuit of thicknesssubstantially equal to X inside the cavity, the bare-die IntegratedCircuit configured to output a millimeter-wave signal from electricallyconductive contacts on an upper side edge of the die; the die is placedinside the cavity such that the portions of the electrically conductivepads and the upper side edge containing the electrically conductivecontacts are closely arranged side-by-side at substantially the sameheight. Wire-bonding each electrically conductive contact to one of theportions of the electrically conductive pads using a bonding wire tobridge a small distance formed between the electrically conductivecontacts and the portions of the electrically conductive pads whenplacing the bare-die Integrated Circuit inside the cavity.

In one embodiment, the electrically conductive pads comprise threeelectrically conductive pads 712 a, 712 b, 712 c, printed on one of thelaminas 709 of the PCB, the portions 712 a′, 712 b′, 712 c′ of the threeelectrically conductive pads 712 a, 712 b, 712 c operative tosubstantially reach the edge 713 of the cavity. The bare-die IntegratedCircuit 725 is configured to output a millimeter-wave signal from threeelectrically conductive contacts 728 a, 728 b, 728 c arranged in aground-signal-ground configuration on the upper side edge of the die.Three bonding wires 727 a, 727 b, 727 c or strips are used to wire-bondeach electrically conductive contact 728 a, 728 b, 728 c to one of theportions 712 a′, 712 b′, 712 c′ of the electrically conductive pads 712a, 712 b, 712 c.

FIG. 27D, FIG. 27E, FIG. 27F, FIG. 27G, and FIG. 27H illustrate oneembodiment of a method for interfacing a bare-die Integrated Circuitwith a PCB, in accordance with some embodiments. Electrically conductivepads 712 a, 712 b, 712 c are printed on lamina 709 of a PCB 715. Acavity 720 b of depth equal to X is formed in the PCB 715. At least oneof the cuts used to form the cavity, also cuts through the electricallyconductive pads 712 a, 712 b, 712 c the at least one cut is denoted bynumeral 721, such that portions 712 a′, 712 b′, 712 c′ of theelectrically conductive pads 712 a, 712 b, 712 c, still remaining on thePCB, reach an edge 713 of the cavity 720 b, and the other portions 714are removed from the PCB. A bare-die Integrated Circuit 725 of thicknesssubstantially equal to X is placed inside the cavity 720 b, such thatthe remaining portions 712 a′, 712 b′, 712 c′ of pads 712 a, 712 b, 712c and an upper side edge containing electrically conductive contacts 728a, 728 b, 728 c of the bare-die Integrated Circuit 725 are closelyarranged side-by-side at substantially the same height, in accordancewith some embodiments. The electrically conductive contacts are thenwire-bonded to the remaining portions 712 a′, 712 b′, 712 c′ of theelectrically conductive pads 712 a, 712 b, 712 c using short bondingwires 727 a, 727 b, 727 c.

In one embodiment, a probe 712 is printed on the same lamina 709 as theportion 712 b′ of electrically conductive pad 712 b connected to theelectrically conductive contact 728 b associated with the signal. Atransmission line signal trace 712 d is printed as a continuation to theportion 712 b′ of electrically conductive pad 712 connected toelectrically conductive contact 728 b associated with the signal, thetransmission line signal trace 712 d electrically connectingelectrically conductive contact 728 b associated with the signal to theprobe 712.

In one embodiment, the electrically conductive pads comprise twoelectrically conductive pads, printed on one of the laminas of the PCB,the portions 733, 734 of the two electrically conductive pads operativeto substantially reach the edge of the cavity. A bare-die IntegratedCircuit is configured to output a millimeter-wave signal from twoelectrically conductive contacts arranged in a differential signalconfiguration on the upper side edge of the die in accordance with someembodiments. Two bonding wires 735 a, 735 b or strips are used towire-bond each electrically conductive contact to one of the portions733, 734 of the electrically conductive pads, in accordance with someembodiments.

In one embodiment, a probe 733 c, 734 c is printed on the same lamina asthe portions 733, 734 of electrically conductive pads connected toelectrically conductive contacts in accordance with some embodiments. Aslot-line transmission line 733 b, 734 b is printed as a continuation toportions 733, 734 of the electrically conductive pads, the slot-linetransmission line 733 b, 734 b electrically connecting the electricallyconductive contacts to the probe 733 c, 734 c.

In one embodiment, a laminate waveguide structure is embedded in thelaminas of the PCB 715 and the probe 712 is located above the laminatewaveguide structure, in accordance with some embodiments. In oneembodiment, the laminate waveguide structure includes cavity 703 inaccordance with some embodiments.

FIG. 28A is a flow diagram illustrating one method of constructinglaminate waveguide structures within a PCB, comprising the followingsteps: In step 1001, creating a first pressed laminate structurecomprising a cavity. In step 1002, plating the cavity with electricallyconductive material. In step 1003, pressing the first laminatestructure, with additional laminas comprising a probe, into a PCBcomprising the probe located above the cavity.

FIG. 28B is a flow diagram illustrating one method of constructing asystem comprising a bare-die Integrated Circuit and a PCB, comprisingthe following steps: In step 1011, creating a first pressed laminatestructure comprising a cavity. In step 1012, plating the cavity withelectrically conductive material. In step 1013, drilling holes inadditional laminas comprising a probe. In step 1014, pressing the firstpressed laminate structure, with the additional laminas, into a PCBcomprising the probe located above the cavity and a second cavity formedby the holes and sealed in the PCB. In step 1015, opening the sealedsecond cavity and inserting a bare-die Integrated Circuit into thecavity.

FIG. 28C is a flow diagram illustrating one method of interfacingbetween a bare-die Integrated Circuit and a PCB, comprising thefollowing steps: In step 1021, printing electrically conductive pads ona PCB. In step 1022, forming a cavity of depth equal to X in the PCB,the act of forming the cavity also cuts through the electricallyconductive pads, leaving portions the electrically conductive pads thatreach an edge of the cavity. In step 1023, placing a bare-die IntegratedCircuit of thickness substantially equal to X inside the cavity, suchthat electrically conductive contacts on an upper side edge of thebare-die Integrated Circuit are placed side-by-side with the portions ofthe electrically conductive pads. In step 1024, using bonding wires orstrips to wire-bond the electrically conductive contacts with theportions of the electrically conductive pads.

In one embodiment, the physical dimensions of millimeter-wave structuresor components described in some embodiments, such as laminatewaveguides, discrete waveguides, transmission line printed traces,transmission line substrates, backshort surfaces, and bare-dieIntegrated Circuits, are optimized for operation in the 57 GHz-86 GHzband.

In this description, numerous specific details are set forth. However,the embodiments/cases of the invention may be practiced without some ofthese specific details. In other instances, well-known hardware,materials, structures and techniques have not been shown in detail inorder not to obscure the understanding of this description. In thisdescription, references to “one embodiment” and “one case” mean that thefeature being referred to may be included in at least oneembodiment/case of the invention. Moreover, separate references to “oneembodiment”, “some embodiments”, “one case”, or “some cases” in thisdescription do not necessarily refer to the same embodiment/case.Illustrated embodiments/cases are not mutually exclusive, unless sostated and except as will be readily apparent to those of ordinary skillin the art. Thus, the invention may include any variety of combinationsand/or integrations of the features of the embodiments/cases describedherein. Also herein, flow diagrams illustrate non-limitingembodiment/case examples of the methods, and block diagrams illustratenon-limiting embodiment/case examples of the devices. Some operations inthe flow diagrams may be described with reference to theembodiments/cases illustrated by the block diagrams. However, themethods of the flow diagrams could be performed by embodiments/cases ofthe invention other than those discussed with reference to the blockdiagrams, and embodiments/cases discussed with reference to the blockdiagrams could perform operations different from those discussed withreference to the flow diagrams. Moreover, although the flow diagrams maydepict serial operations, certain embodiments/cases could performcertain operations in parallel and/or in different orders from thosedepicted. Moreover, the use of repeated reference numerals and/orletters in the text and/or drawings is for the purpose of simplicity andclarity and does not in itself dictate a relationship between thevarious embodiments/cases and/or configurations discussed. Furthermore,methods and mechanisms of the embodiments/cases will sometimes bedescribed in singular form for clarity. However, some embodiments/casesmay include multiple iterations of a method or multiple instantiationsof a mechanism unless noted otherwise. For example, when a controller oran interface are disclosed in an embodiment/case, the scope of theembodiment/case is intended to also cover the use of multiplecontrollers or interfaces.

Certain features of the embodiments/cases, which may have been, forclarity, described in the context of separate embodiments/cases, mayalso be provided in various combinations in a single embodiment/case.Conversely, various features of the embodiments/cases, which may havebeen, for brevity, described in the context of a single embodiment/case,may also be provided separately or in any suitable sub-combination. Theembodiments/cases are not limited in their applications to the detailsof the order or sequence of steps of operation of methods, or to detailsof implementation of devices, set in the description, drawings, orexamples. In addition, individual blocks illustrated in the figures maybe functional in nature and do not necessarily correspond to discretehardware elements. While the methods disclosed herein have beendescribed and shown with reference to particular steps performed in aparticular order, it is understood that these steps may be combined,sub-divided, or reordered to form an equivalent method without departingfrom the teachings of the embodiments/cases. Accordingly, unlessspecifically indicated herein, the order and grouping of the steps isnot a limitation of the embodiments/cases. Embodiments/cases describedin conjunction with specific examples are presented by way of example,and not limitation. Moreover, it is evident that many alternatives,modifications and variations will be apparent to those skilled in theart. Accordingly, it is intended to embrace all such alternatives,modifications and variations that fall within the spirit and scope ofthe appended claims and their equivalents.

1. A system configured to match impedances of a bare-die IntegratedCircuit and bonding wires, comprising: a bare-die Integrated Circuit ora heightened bare-die Integrated Circuit, configured to output or input,at an impedance of Z3, a millimeter-wave signal from three electricallyconductive contacts arranged in a ground-signal-ground configuration onan upper side edge of the bare-die Integrated Circuit; the spacingbetween center point of the electrically conductive contact of thesignal to each center points of the electrically conductive contact ofthe ground is between 100 and 250 microns; three electrically conductivepads, printed on one of the laminas of a Printed Circuit Board (PCB),arranged in a ground-signal-ground configuration alongside the upperside edge of the bare-die Integrated Circuit, and connected to the threeelectrically conductive contacts via three bonding wires respectively,the bonding wires having a characteristic impedance of Z1, whereinZ1>Z3; the electrically conductive pad of the signal extends to form atransmission line signal trace of length L, the transmission line signaltrace having a first width resulting in characteristic impedance of Z2,wherein Z2>Z3; and the transmission line signal trace widens to a secondwidth, higher than the first width, after the length of L, operative todecrease the characteristic impedance of the transmission line signaltrace to substantially Z3 after the length L and onwards, where Z3 is atmost 70% of Z2 and Z3 is at most 70% of Z1; the system configured tomatch an impedance seen by the bare-die Integrated Circuit at theelectrically conductive contacts with the impedance Z3, by determiningL.
 2. The system of claim 1, further comprising: a cavity of depth X,formed in the PCB, going through at least one lamina of the PCB; whereinthe three electrically conductive pads are printed on one of the laminasof the PCB, the electrically conductive pads operative to substantiallyreach the edge of the cavity; the bare-die Integrated Circuit or theheightened bare-die Integrated Circuit is of thickness X, and thebare-die Integrated Circuit or the heightened bare-die IntegratedCircuit is placed inside the cavity such that the electricallyconductive pads and the upper side edge containing the electricallyconductive contacts are arranged side-by-side at substantially sameheight; and the system configured to transport a millimeter-wave signalbetween the electrically conductive contacts and the electricallyconductive pads across a distance of less than 500 microns, formedbetween each electrically conductive contact and correspondingelectrically conductive pad.
 3. The system of claim 1, wherein the twoelectrically conductive pads connected to the electrically conductivecontacts of the ground are electrically connected, through VerticalInterconnect Access holes, to a ground layer below the electricallyconductive pads, wherein the ground layer together with the transmissionline signal trace form a Microstrip transmission line.
 4. The systemclaim 1, wherein the same lamina used to carry the transmission linesignal trace and electrically conductive pads on one side, is the laminaused to carry the ground layer on the opposite side, and the lamina usedto carry the transmission line signal trace is made out of a softlaminate material suitable to be used as a millimeter-wave bandsubstrate in PCB.
 5. The system of claim 4, wherein the system isoperative to transport the millimeter-wave signal belonging to afrequency band between 20 GHz and 100 GHz, from the electricallyconductive contact of the signal to the transmission line signal trace.6. The system of claim 4, wherein Z1 is between 75 and 160 ohm, Z2 isbetween 75 and 160 ohm, and Z3 is substantially 50 ohm.
 7. The system ofclaim 6, wherein the spacing between the center point of theelectrically conductive contact associated with the signal to each ofthe center points of the electrically conductive contact associated withthe ground, is substantially 150 microns, the width of the transmissionline signal trace up to length L is between 65 and 85 microns, and thespacing between the transmission line signal trace up to length L andeach of the electrically conductive pads of the ground is between 65 and85 microns.
 8. The system claim 1, wherein the length L is determinedsuch that the cumulative electrical length, up to the point where thetransmission line signal trace widens, is substantially one half thewavelength of the millimeter-wave signal transmitted via theelectrically conductive contact of the signal.
 9. The system of claim 1,wherein the two electrically conductive pads connected to theelectrically conductive contacts of the ground are electricallyconnected, using capacitive pad extensions, to a ground layer below theelectrically conductive pads, wherein the ground layer together with thetransmission line signal trace form a Microstrip transmission line. 10.The system of claim 1, wherein a capacitive thickening along thetransmission line signal trace, and before the transmission line signaltrace widens, is added in order to reduce the length L needed to matchthe impedance seen by the bare-die Integrated Circuit at theelectrically conductive contacts with the impedance Z3.
 11. A systemconfigured to match impedances of a bare-die Integrated Circuit andbonding wires, comprising: a bare-die Integrated Circuit or a heightenedbare-die Integrated Circuit, configured to output or input, at animpedance Z3, a millimeter-wave signal from two electrically conductivecontacts arranged in a side-by-side differential signal configuration onan upper side edge of the bare-die Integrated Circuit; two electricallyconductive pads, printed on one of the laminas of a Printed CircuitBoard (PCB), arranged alongside the upper side edge of the bare-dieIntegrated Circuit, and connected to the two electrically conductivecontacts via two bonding wires respectively, the wires having acharacteristic impedance of Z1, wherein Z1>Z3; the two electricallyconductive pads extend to form a slot-line transmission line of lengthL, having a characteristic impedance of Z2, wherein Z2>Z3; and theslot-line transmission line configured to interface with a secondtransmission line having a characteristic impedance seen by theslot-line transmission line as substantially Z3; the system configuredto match an impedance seen by the bare-die Integrated Circuit at theelectrically conductive contacts with the impedance Z3, by determiningL.
 12. The system of claim 11, further comprising: a cavity of depth X,formed in the PCB, going through at least one lamina of the PCB; whereinthe two electrically conductive pads are printed on one of the laminasof the PCB, the electrically conductive pads operative to substantiallyreach the edge of the cavity; the bare-die Integrated Circuit or theheightened bare-die Integrated Circuit is of thickness X, and thebare-die Integrated Circuit is placed inside the cavity such that theelectrically conductive pads and the upper side edge containing theelectrically conductive contacts are arranged side-by-side atsubstantially same height; and the system configured to transport amillimeter-wave signal from the electrically conductive contacts to theelectrically conductive pads across a small distance of less than 500microns, formed between each electrically conductive contact andcorresponding electrically conductive pad.
 13. The system claim 11,wherein the lamina used to carry the slot-line transmission line is madeout of a soft laminate material suitable to be used as a millimeter-waveband substrate in PCB.
 14. The system of claim 13, wherein the system isoperative to transport the millimeter-wave signal belonging to afrequency band between 20 GHz and 100 GHz, from the electricallyconductive contacts to the slot-line transmission line.
 15. The systemof claim 13, wherein Z1 is between 120 and 260 ohm, Z2 is between 120and 260 ohm, and Z3 is substantially two times 50 ohm.
 16. The systemclaim 11, wherein the length L is determined such that the cumulativeelectrical length, up to the end of the slot-line transmission line, issubstantially one half the wavelength of the millimeter-wave signaltransmitted via the electrically conductive contacts.
 17. The system ofclaim 11, wherein the second transmission line is a Microstrip, and theinterface comprises balanced-to-unbalanced signal conversion.
 18. Thesystem of claim 17, wherein Z1 is between 120 and 260 ohm, Z2 is between120 and 260 ohm, Z3 is substantially two times 50 ohm, and theMicrostrip has a characteristic impedance of substantially 50 ohm.